Intercalated clay having large interlayer spacing

ABSTRACT

Hydrothermally stable intercalated clays having interlayer (gallery) spacings greater than 21 angstroms are provided by pillars comprising a rare earth metal. The pillars preferably also contain a metal such as aluminum. Other pillaring metal/rare earth combinations and differing preparation conditions, such as pH, result in different interlayer spacings. Interlayer spacings of up to 50 angstroms may be produced.

CROSS REFERENCE TO RELATED APPLICATION

This application is a continuation-in-part of application Ser. No.07/583,788 filed Sept. 17, 1990 (now U.S. Pat. No. 5,059,568) which is acontinuation-in-part of application Ser. No. 304,319 filed Jan. 31,1989, now U.S. Pat. No. 4957889) which was a continuation-in-part ofapplication Ser. No. 021,972, filed Mar. 5, 1987 (now U.S. Pat.4,952,544).

Field of The Invention

The invention relates to intercalated clays and to methods of preparingsuch intercalated clays.

This invention also relates to alumina oligomers used in the preparationof the aforementioned intercalated clays which also demonstrateindependent utility.

Layered naturally occurring and synthetic smectites, such as bentonite,montmorillonites and hecorites, may be visualized as a "sandwich"composed of two outer layers of silicon tetrahedra and an inner layer ofalumina octahedra. These "sandwiches" or platelets are stacked one uponthe other to yield a clay particle. Normally this arrangement yields arepeated structure about every nine and one-half angstroms. Pillared orintercalated clays are produced by the insertion of "pillars" ofinorganic oxide material between these layers to provide a larger spacebetween the natural clay layers.

The subject invention relates to the production of pillared clays havinga wider layer spacing, and increased hydrothermal stability, as comparedto prior art pillared clays.

Prior Art

U.S. Pat. No. 4,753,909 issued to Jacques Bousquet et al. (assigned toElf France, equivalent to Belgium Patent 905,662 of Feb. 16, 1987)describes "bridged" clays having improved thermal stability and usefulas cracking catalysts. The materials of this reference do not appear tohave the interlayer spacing of clays of the subject invention.Furthermore, the subject pillared clays have pillars formed of bothspecified pillaring metals and a separate rare earth which confersexceptional hydrothermal stability and surface area retention whenexposed to high temperature steam.

Intercalated clays have been prepared by replacing the exchangeablecations of the original clay with aluminum oligomers [U.S. Pat. No.4,176,090; U.S. Pat. No. 4,248,739; U.S. Pat. No. 4,216,188; Lahav. N.,Shani. U., and Shabtai. J. S., Clay and Clay Minerals, 1978, 26(2), 107;Lahav. N.. and Shani. U., Clay and Clay Minerals, 1978, 26(2), 116; andBrindley, G. W., and Sempels. R. E., CIay Minerals, 1977, 12, 229]Zirconium oligomers [Yamanaka. S.. and Brindly. G. W., Clay and ClayMinerals, 1979, 27(2), 119] and chromium oligomers (U.S. Pat. No.4,452,901). The concept used is that aluminum cations hydrolyze and,through the addition of base to increase pH (see U.S. Pat. No.4,176,070, Examples 16 and 21 and column 4, line 9), an oligomer oflarge molecular weight would form. Information on the deactivation andregeneration behavior of these catalysts is not well documented,however, it is generally recognized that they are not hydrothermallystable. (Imelik. B., et al., "Catalysis by Acids and Bases", ElsevierScience Publishers, Amsterdam, The Netherlands, 1985; and Occelli. M.L., Ind. Eng. Chem. Prod. Res. Dev., 1983, 22, 553).

It is known that 2:1 layered clays (e.g., bentonite, montmorillonite,and hectorite) can be intercalated to yield catalysts that exhibitactivity and selectivity. The problem of insufficient thermal andhydrothermal stability of these clays is also well known (see Occelli.Marlo L., ibid., 533-559 and FIGS. 4 and 5). The pillars of these clayscollapse at temperatures of over 650° C. due to dehydroxylation andpossible cation migration replacing aluminum.

Of the above-mentioned oligomers, aluminum oligomers have apparentlybeen researched the most extensively. These oligomers can be formed in avariety of ways involving hydrolysis of the aluminum cation and arecommercially available. During hydrolysis many cationic species areformed. Their equilibrium concentrations are very dependent upontemperature and pH. The maximum concentration of a desired species maybe in a very narrow range of these variables. In addition, the speciescannot be easily isolated or identified. If conditions are favorable,hydrolysis of the aluminum cation will proceed to form highly chargedspecies [e.g., Al₂ (OH)₂ ⁴⁺, Al₃ (OH)₄ ⁵⁺ and Al₁₃ O₄ (OH)₂₄ ⁷⁺ ] (SeeBaes. C. F., Jr., and Mesmer. R. E., "The Hydrolysis of Cations", JohnWiley and Sons, Inc., New York, N.Y., 1976 Of particular interest is thecation Al₁₃ O₄ (OH)₂₄ ⁷⁺. From NMR studies, this species has been foundto be the oligomer species responsible for the typical d₀₀₁ spacing of18 Å in intercalated clays, (Plee, D., et al., J. Am. Chem. SOC. 1985,107, 2362). The structure of this cation is a central four-coordinatedaluminum atom surrounded by twelve AlO₆ octahedra joined by common edgesto form a Keggin-type structure. Because of its large charge and size itcan easily replace exchangeable cations from the clay. Upon heating thisoligomer forms a pillar of alumina yielding an intercalated clay withthe characteristic d001 spacing with 18 Å. At temperatures above 650°C., dehydroxylation occurs and the pillars collapse (i.e., the intensityof d₀₀₁ =18 Å disappears).

Lahav. N.. Shani. U.. and Shabtai. J. S., ibid., p. 108, discloses thatin the in situ formation method, the relevant metal cation is introducedinto the clay exchange complex followed by in situ transformation intothe hydroxide by raising the pH. In the crosslinking method, the metalhydroxide oligomer polymorph) is prepared separately and then interactedwith the clay particles, leading to the formation of a crosslinkedframework. Application of the in situ method, which can be considered asa simulated natural process, leads to slow, gradual formation of theinterlayered structure, whereas in the crosslinking method, the metalhydroxide oligomers crosslink the clay platelets in a fast reaction andthe product is obtained almost instantaneously. If a freshly preparedmetal hydroxide solution is used in the crosslinking method, both the insitu sequence and crosslinking probably take place, since the formationof stable oligomeric species is a slow process.

U.S. Pat. No. 4,510,257 (Lewis et al.) discloses a clay compositionhaving silica pillars intercalated between the layers of an expandable,swelling layer, lattice clay mineral or synthetic analogue thereof. Thesilica pillars have at least two silicon atom layers. The claycomposition is prepared by contacting a smectite type clay with asolution of a polyhedral oligosilsesquioxane of the following generalformula (ZSiO₁.5)_(n) (OSiZ₂)_(m), wherein n and m are zero or integersand n+m does not equal zero and Z is an organic moiety containing anatom(s) possessing cationic and/or coordinating characteristics with theproviso that all of the Z's on a particular oligosilsesquioxane need notbe the same. A cracking catalyst is disclosed which is the silicaintercalated clay product functionalized with ions which are hydrogen orthe rare earth elements.

U.S. Pat. No. 4,176,090 (Vaughan et al. I) discloses pillaredinterlayered clay compositions which are prepared by reactingsmectite-type clays with polymeric cationic hydroxo metal complexes ofmetals such as aluminum, zirconium and/or titanium. The interlayeredclay compositions which possess substantial surface area in pores ofless than 30 Å in diameter are used as catalysts, catalytic supports andsorbents. The interlayered smectite can be prepared by reacting asmectite with a mixture of a polymeric cationic hydroxo inorganic metalcomplex, which is comprised of aluminum or zirconium complexes ormixtures thereof, plus water. The interlayered smectite is separatedfrom the mixture. Column 6, lines 28 to 32, discloses that theintercalated clays are particularly useful in the preparation ofcatalysts which contain active/stabilizing metals such as platinum,palladium, cobalt, molybdenum, nickel, tungsten, rare earths and soforth.

U.S. Pat. No.4,271,043 (Vaughan et al. II) is a continuation-in-part ofU.S. Pat. No. 4,176,090 and also discloses the use of thecopolymerization of ammonium and alkali metal hydroxides, carbonates,silicate and borate. Vaughan et al. II describes a process for preparinga pillared interlayered clay product having a high degree of ionexchange capacity. A smectite clay is reacted with a mixture of apolymeric cationic hydroxo metal complex, such as, polymeric cationichydroxo aluminum and zirconium complexes, and water to obtain a pillaredinterlayered smectite. The interlayered smectite is calcined to obtainan interlayered clay product having greater than 50 percent of itssurface area in pores less than 30 Å in diameter. The calcinedinterlayered clay product is reacted with a base to increase the ionexchange capacity thereof. Some of the examples show the calcinedinterlayered clay being impregnated or exchanged using La(NO₃)₃ orLaCl₃.

U.S. Pat. No. 4,248,739 (Vaughan et al. III) is a continuation-in-partof U.S. Pat. No. 4,176,090. Vaughan et al. III discloses a method forpreparing a pillared interlayered smectite clay product wherein asmectite clay is reacted with a mixture of polymeric cationic hydroxometal complex and water to obtain a pillared, interlayered smectitehaving greater than 50 percent of its surface area in pores of less than30 Å in diameter after dehydration. The polymeric cationic hydroxo metalcomplex is a high molecular weight cationic hydroxo metal complex andcopolymers thereof having a molecular weight of from about 2000 to20,000. Example 3 hydrolyzes and polymerizes the aluminum chlorhydroxideby the addition of magnesium metal. Example 4 prepared a mixed Al-Mgpolymer for pillaring interlayered smectite by dissolving AlCl₃.6H₂ Oand MgCl₂.H₂ O in deionized water and drying at 250° F.

U.S. Pat. No. 4,452,910 (Hopkins) discloses a process for thepreparation of stabilized, porous expanded layer, smectite clays. Anaqueous slurry of smectite clay is contacted with an agedchromium-oligomer solution. A product clay is separated from themixture. The product clay is dried, and is then stabilized by an inertgas atmosphere heat treatment, which includes a temperature above about200° C. to effect the production of a stabilized clay. The product is aporous catalytic material composed of a smectite clay having expandedmolecular layers with a multiplicity of chromium-base "pillars"interposed between the molecular layers of the smectite clay.

U.S. Pat. No. 4,216,188 (Shabtai et al. I) discloses a process for theproduction of molecular sieves by reacting a colloidal solution of amonoionic montmorillonite having a concentration of 100 to 800 mgmontmorillonite per liter, in the form of fully dispersed negativelycharged unit layers at room temperature, with an aged sol of a metalhydroxide which has been aged for at least 5 days at ambienttemperature. The metal hydroxide is aluminum hydroxide or chromiumhydroxide. The reaction is conducted at a pH adjusted below the zerocharge point having a residual net positive charge on the metalhydroxide, and under vigorous agitation, resulting in a rapidflocculation of the montmorillonite crosslinked with the metalhydroxide. The product is separated from the liquid phase and stabilizedby heat treatment.

U.S. Pat. No. 4,238,364 (Shabati II) describes a cracking catalystcomprising a crosslinked smectite framework material functionalized withacid ions selected from the group consisting of the ions of hydrogen andrare earth elements. The preparatory method includes: preparing anacidic form of smectite clay including ions selected from the groupconsisting of hydrogen, cerium, gadolinium, lanthanum, neodymium,praseodymium, and samarium; crosslinking the acid form of smectite witholigomeric species of aluminum hydroxide; and stabilizing thecrosslinked acidic form of smectite. Column 4, lines 15 to 23, ofShabtai II explains the difference between interlayer and lateraldistance. As explained on line 54 of column 4, Shabtai II has obtainedan interlayer spacing of 9 Å. The lateral distance of 8 to 30 Åmentioned in Shabtai II is the distance between the pillars ascalculated by the ratio of reactant to clay (i.e., fully or partiallyreacted clay). In claim 12 Shabtai II clarifys the matter of the 8 to 30Å as being the lateral distance in the interlayer space so as to providea measure of the effective lateral (between the pillars, not between thelayers of the clay) pore size. Referring to the drawings and col. 4,lines 15 to 23, the lateral distance (E) is termed the interpillardistance.

U.S. Pat. No. 4,579,832 (Shabtai et al.) describes a hydroprocessingcatalyst possessing activity hydrocracking and/or hydrogenationactivity. The catalyst includes a cross-linked smectite frameworkmaterial prepared through interaction of the polyanionic smectite layerswith oxygen containing oligomeric cations, that is, oligomeric hydroxometal cations or oxo-metal cations. The catalyst also includesincorporated interlamellar components consisting of preselectedcombinations of catalytically active transition metal derivativesselected from the group consisting of Mo, Cr, Ni, Co, W and othertransition metals. The transition metals are present in the form ofmetal derivatives selected from the group consisting of oxygencontaining oligomers and oligomeric cations, and cations selected fromthe group consisting of mononuclear cations and binuclear cations. Thecatalysts can have lateral pore sizes of 11 to 35 Å. Since Shabtai etal. used hydroxo aluminum oligomer, its intercalated clays had aninterlayer distance of about 9 Å.

U.S. Pat. No. 4,753,909 (Bousquett et al) teaches clays of limitedstructure bridged by metallic oxides selected from oxides of aluminumand zirconium and containing from 10 to 50% and preferrably 20-40% of anoxide of the metal of the group of lanthanides, preferably of cerium.The metallics produced have relatively no hydrothermal stability asshown by the data provided and require an extraordinarily high molpercent cerium.

Shabtai. J., F. E. Massoth. M. Tokarz. G. M. Tsai and J. McCauley, 8thInternational Congress On Catalysts, (July 2-6, 1984), Proceedings, Vol.IV, pp. 735-745, discloses a series of cross-linked hydroxo-A1montmorillonite having basal spacings of 1.75 to 1.95 nm and surfaceareas of 300 to 500 m² /g after heat treatment at temperatures of up to873° K. The series of pillared clay was in Ce³⁺ -, La³⁺ -, Li⁺ - and Na⁺/Ca²⁺ -forms. The first three forms were formed by ion exchanging Na⁺/Ca²⁺ -montmorillonite with aqueous solutions of CeCl₃, LaCl₃, LaCl₃ andLiCl, respectively. The pillared clays had catalytic cracking activity.Details of some of the techniques and procedures were stated to be inMcCauley. J., "Catalytic Cracking Properties Of Cross-LinkedMontmorillonite (CLM) Molecular Sieves", MSc. Thesis, University ofUtah, Salt Lake City, Utah (1983).

Tokarz, M. and J. Shabtai, Clays And Clay Minerals, Vol. 3, No. 2,(195), pp. 89-97, discloses partially hydroxo-A1 montmorillonitesprepared by the reaction of hydroxo-A1 oligocations with Ce³⁺ - and La³⁺-exchanged montmorillonites.

U.S. Pat. No. 4,436,832 (Jacobs et al.) relates to a bridged claycatalyst and a method of making it. The method consists of subjecting amixture of an aqueous solution of at least one metal hydroxide andaqueous clay suspension to dialysis. (The hydroxide solution can beprepared before it is mixed with the clay suspension or by adding thehydroxide solution precursors to the clay suspension.) The clay catalystis used for conversion of paraffinic or olefinic hydrocarbons. Thehydroxides can be selected from the group formed by the hydroxides ofthe elements of groups IIB, IIIB, IVB, VB, VIB, VIIB, VIIIB, IA, IIA,IIIA, IVA, VA and VIA of the periodic table of the elements. Example 4uses Ho(NO₃)₃.6H₂ O.

Pinnavia. T. J., "Intercalated Clay Catalysts", Science, Vol. 220, pp.365-371, (1983) describes that intercalation of polynuclear hydroxometal cations and metal cluster cations in smectites to produce pillaredclay catalysts having large size pores. Page 366, while not dealing withpillaring, states that the hydrated cations on the interlamellersurfaces of the native minerals can be replaced with almost any desiredcation by utilizing simple ion exchange methods and that homoionicexchange derivatives are readily achievable with simple hydratedcations, including hydrated transition metal ions. Pinnavia also statedthat, although polynuclear hydroxo metal ions formed by hydrolysis inaqueous solution can yield pillared clays with interlayer free spacings,the number of metals that form suitable oligomeric species is limited.New approaches to the pillaring of smectite clays promise to extend thenumber of pillaring species. Page 371 states that an approach involvinghydrolysis and oxidation of metal cluster cations, such as Nb₆ C₁₂ ²⁺and Ta₆ C₁₂ ²⁺, affords clay pillared by small custers of metal oxideapproximately 10 in diameter and stable to about 400° C.

Japanese Kokai 58-55,332 shows a heat-resistant modified smectite claycatalyst with a large surface area, having a trinuclear ferric acetatecation. This clay catalyst is prepared by using bentonite modifiedmontmorillonite in aqueous solution.

Pinnavia, T. J., "New Chromia Pillared Clay Catalysts", J. Am. Chem.Soc. (1985) 107, pp. 4783-4785 describes a method of making chromiapillared clays wherein solutions containing cationic polyoxychromiumoligmers were prepared by the hydrolysis of chromium nitrate using Na₂CO₃ as the base. To this solution was added typical smectite. Chromiumwas maintained in large excess during the pillaring reaction and after areaction time of 1.5 hours, products were collected by centrifugationand washed free of excess salt.

Chemical Abstracts, 104:96367×(1986), states that Zr-pillared clays aremore stable than equivalent A1-pillared clays. Chemical Abstracts.104:88077e (1986), also deals with Zr-containing pillared interlayerclays. Chemical Abstracts. 104: 50491×(1986), states that, in theconversion of trimethylbenzenes, the selectivity of montmorillonitespillared by aluminum and zirconium oxides is not dependent uponinterlayer distance. Chemical Abstracts, 102:45425h (1985), deals withpillaring smectite clay using polyoxo cations of aluminum.

BRIEF SUMMARY OF THE INVENTION

The invention provides a novel intercalated or pillared claycharacterized by a large interlayer spacing and also by excellenthydrothermal stability. The clay of the subject invention possesses aninterlayer spacing greater than about 16 angstroms and preferably in therange of about 16 to 18 angstroms. The pillars will contain a rare earthelement, oxygen, and a second metal such as aluminum, zirconium,chromium or iron.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an X-ray diffraction scan of unreacted bentonite;

FIG. 2 is an X-ray diffraction scan of A1-intercalated bentonite;

FIG. 3 is an X-ray diffraction scan of the intercalated bentonite, ofthe invention;

FIG. 4 is a graph of activity versus the weight ratio of catalyst versusfeed oil for various catalysts;

FIG. 5 is a graph of gas-make versus conversion for various catalysts;

FIG. 6 is a graph of gasoline-make versus conversion for variouscatalysts;

FIG. 7 is a graph of light cycle oil (LCO) make versus converion forvarious catalysts;

FIG. 8 is a graph of heavy cycle oil (HCO) make versus conversion forvarious catalysts;

FIG. 9 is a graph of coke make versus activity for various catalysts;

FIG. 10 is a graph of C₄ =/C₄ total versus conversion for severalcatalysts; and

FIG. 11 is a graph of coke versus activity for high and low ironpillared clays.

FIG. 12 is an X-ray diffraction scan of unreacted (raw) fluorhectorite;

FIG. 13 is an X-ray diffraction scan of the intercalated fluorhectoriteof the invention;

FIG. 14 is an X-ray diffraction scan of oligomers prepared from aqueouschlorhydrol;

FIG. 15 is another X-ray diffraction scan of oligomers prepared fromaqueous chlorhydrol;

FIG. 16 is an X-ray diffraction scan of oligomers prepared from anaqueous Ce(NO₃)₃ and chlorhydrol;

FIG. 17 is an X-ray diffraction scan of oligomers prepared from aqueousCe(NO₃)₃ and chlorhydrol;

FIG. 18 is an X-ray diffraction scan of oligomers prepared from aqueousLaCl₃ and chlorhydrol;

FIG. 19 is an X-ray diffraction scan of oligomers prepared from aqueousLaCl₃ and chlorhydrol;

FIG. 20 is an X-ray diffraction scan of oligomers prepared from aqueousCe(NO₃)₃ and chlorhydrol;

FIG. 21 is an X-ray diffraction scan of oligomers prepared from aqueousCe(NO₃)₃ and chlorhydrol; and

FIG. 22 is a schematic illustration of a cross-section of theintercalated clay (bentonite) of the invention.

FIG. 23 is an X-ray diffraction scan of an A1-La oligomer.

FIG. 24 is an X-ray diffraction scan of an A1-Ce oligomer.

FIG. 25 is an X-ray diffraction scan of A1-Pr olgiomer.

FIG. 26 is an X-ray diffraction scan of A1-Nd oligomer.

FIG. 27 is an X-ray diffraction scan of Al olgiomer.

FIG. 28 is an X-ray diffraction scan of pH adjusted Alumina Rare EarthOligomers.

DETAILED DESCRIPTION OF THE INVENTION

The product of the invention is a hydrothermally stable microporouscatalytic material composed of a layered, colloidal clay having expandedmolecular layers with a multiplicity of pillars interposed between themolecular layers of the clay. The pillars, which are themselves noveland exhibit independent utility, are composed of aluminum, at least onerare earth element, oxygen and/or a halogen. The aluminum can bereplaced in part or total by other suitable, pillaring metals, such as,chromium and zirconium. The product has relatively large pores andpossesses considerable internal micropore volume. The intercalated claysof the invention are excellent cracking catalysts for heavy crackingoils. The pillars maintain the spacing of the expanded molecular layersof the clay even at temperatures as high as 1450° F., with theintercalated clay maintaining its surface area and cracking catalyticactivity. The invention material can also be described as a molecularsieve framework prepared by intercalating clay unit layers witholigomeric or polymeric species. Upon intercalation, the material isdried and subjected to heat treatment to stabilize the expanded layers.The open, porous network of the expanded clay is stabilized by theintercalated aluminum-rare earth element-oxygen structures between theinterlayers of the clay. The oligomers are ion exchanged with the clay.The three-dimensional pillars are composed of stable inorganic polymersof (i) aluminum or other pillaring metal(s), (ii) rare earth element(s)and (iii) oxygen and/or halogen. While the pillars preferably containoxides of aluminum, other suitable polyoxocations (for example, of Zrand Cr) can be used.

The term "intercalation" is a term of art which indicates the insertionof a material between the layers of a clay substrate. Leoppert. Jr., etal., Clays and Clay Minerals, 27(3), 201-208 (1979), is an example of areference which uses the term in the same way it is used herein.

The invention is based upon preparing microporous materials byinterlayering expandable, colloidal clay minerals with novel oligomericmolecules derived from trivalent rare earth salts and the hydrolysis ofpolyvalent cations such as Al⁺³. As can be readily seen elsewhereherein, other preparation methods, other pillaring metals and rare earthsalts having other oxidation states can be used. The inventionintercalated clay is activated once it is reacted (formed) and couldthen even be used in slurry form for separations.

The forms of smectite clays with pillars based upon aluminum-oxygen(just aluminum and oxygen) derivatives exhibit d₀₀₁ spacings of about 18Å. Neither spacing is sufficient for large molecules as incur in heavycracking oils. The pillared product will have pore heights generally of16 to 40 Å, although the pore heights can be as low as about 10 Å or aslarge as about 50 Å. (Different clays and pillars will provide differentpore sizes.) A pore height greater than about 21 Å may be desired insome circumstances, and interlayer spacings of about 22-40 Å can beprovided and find utility when large pores or channels are needed. Thepore heights secured with montmorillonite are about 18 Å (which is avery advantageous size). As montmorillonite pillared withaluminum-oxygen oligomers has a pore height (that is, interlayerdistance) of about 8.5 Å, the inclusion of a rare earth element with thealuminum and oxygen in a pillar doubles the expansion over the A1-Opillared clay. This advantage, which is unexpected from the prior artteachings, provides an excellent cracking catalyst for cracking heavyoils and provides a material suitable for use as a sorbent or catalystas described below.

One embodiment of the invention may be characterized an intercalatedsmectite clay having pillars comprising at least one rare earth metaland also characterized by an interlayer spacing greater than about 22but less than about 40 angstroms.

Another embodiment of the invention may be characterized as anintercalated smectite clay having pillars which comprise at least onerare earth metal, said clay characterized by an interlayer spacinggreater than about 21 angstroms.

Yet another embodiment of the invention may be characterized as anintercalated clay having pillars which comprise a rare earth metal and ametal chosen from the group consisting of aluminum, chromium andzirconium and also characterized by an interlayer spacing of about 16-18angstroms.

If there is insufficient reaction in the formation of the inventionpillared clay, some of the pillers may only be of the aluminum-oxygenderivative type with the accompanying local areas or points of smallerd₀₀₁ spacing.

As the feedstocks for refiners become heavier, diffusion restrictions inthe catalyst become more important. For example, the micropore diameterof Y-type zeolites is limited to about 9 Å. This excludes largemolecules, such as those found in heavy residuals, from entering itspore system. Because of diffusion limitations inherent to Y-typezeolites the invention intercalated clay catalysts which exhibitdifferent pore sizes and geometries from Y-type zeolites were developed.The invention catalysts have increased LCO selectivity, and exhibitimproved bottoms cracking relative to Y-type zeolites.

The trend in the industry is to use heavier crudes having largermolecules and higher boiling temperatures (ranges), so more coke isinherently formed and, accordingly, higher temperatures are needed toburn off the deposited coke. This means that the industry needscatalysts which are more thermally stable.

The clays useful in the invention are crystalline, expandable, colloidalclays or clay minerals, and have ion exchange capacity. The clays shouldbe of the three-layer type, namely, sheet structures composed of twolayers of silica tetrahedrons and one central alumina dioctahedral ortrioctahedral layer. This type of clay includes equidimensionalexpanding lattice forms (e.g., the montmorillonite groups, such as,montmorillonite and sauconite) and the elongate expanding lattice forms(e.g., the montmorillonite groups, such as nontronite, saponite andhectorite). Vermiculite is believed to not be useful in the invention.The useful clays can be natural or synthetic forms.

The invention is especially useful with clays which are swellable claysgenerally known as smectites. The unit layer of smectite, such as,montmorillonite, is composed of two silica tetrahedral sheets and acentral alumina octahedral sheet. (Such type of clay is termed a 2:1layered clay.) The simplified formula, without considering latticesubstitutions, is Si₈ Al₄ O₂₀ (OH)₄.nH₂ O, wherein n is usually a wholenumber. In reality, however, there are isomorphic substitutions withinthe lattice, e.g., replacement of aluminum by magnesium or iron, and inparticular, substitution of silicon by aluminum. The leads to a netnegative charge on the smectite layers which is compensated for byexchangeable cations situated between the unit layers.

The intercalated or bridged clays of the invention possesses catalyticactivity and catalytic selectivity which are superbly suitable for thecracking of heavy feed stocks. The invention provides catalysts withgreater light cycle oil (LCO) selectivity and bottoms cracking thanY-type zeolites. In addition, the invention catalysts can be synthesizedfrom inexpensive, commercially-available materials using a simpleprocess. The intercalated clay/zeolite of the invention is a compatiblesystem exhibiting desirable synergisms (e.g., less C₁ -C₄ and moregasoline).

The invention provides hydrothermally stable cracking catalysts withlarger pore diameters than conventional zeolites, as is required for thecracking of heavy feed stocks.

An advantage of the product of the invention is that it does not have tobe stabilized by means of thermal treatment in an inert gas atmosphere.The intercalated clay is active upon being formed--the follow up stepsare to drive off the solvent and to stabilize the product.

The hydrothermally stable intercalated clays of the invention do nothave the prior art problem of their pillars collapsing at over thedehydroxylation temperature. The invention intercalated clays havecommercial potential as hydrothermally stable large pore materials.

Another embodiment of the invention is that the invention intercalatedclays contain different catalytic combinations and/or ions which havebeen incorporated inside of the interlamellar space thereof. Or in otherwords, catalytic activity is provided in such interlamellar space byincorporating essential components consisting of different catalyticallyactive transition metal derivatives or combinations thereof, such as,hydroxo-M or sulfhydro-M oligomers or oligomeric cations (where M is oneor different combinations of molybdenum, chromium, nickel, cobalt,tungsten or other transition metal), and/or simple mono or binucleartransition metal ions, such as, those of nickel, cobalt, molybdenum,chromium or other transition metals in such interlamellar space. Thisembodiment of the invention provides hydrothermally-stablehydroprocessing catalysts. Such invention catalysts possess highactivity for hydrotreatment and/or hydrocracking of organic moleculespresent in heavy petroleum fractions, synthetic fuels and other heavyoils have the high catalytic activity of this invention for bulkyorganic molecules (kinetic diameters, 10 to 30 Å. The lateral pore sizeof the invention can range generally from about 11 to about 35 byvarying the amount of oligomer and clay in the preparation of theintercalated clay.

The clay used in preparing the intercalated clay can be ion exchangedwith at least transition metal. Alternatively, the oligomers used inpreparing the intercalated clay can be isomorphically substituted withat least one transition metal during the formation of the oligomers. Theintercalated clay, that is, its pillars and clay layers, can be ionexchanged or isomorphically substituted with at least one transitionmetal. This can be achieved by, for example, preparing a solution of asoluble compound, such as a sulfide, of at least one transition metal ina solvent, such as water, and reducing at least one transition metalcompound with at least one reducing agent, such as hydrogen.

The invention also includes a hydroprocessing catalyst composition of0.1 to about 40 weight percent of at least one zeolite and about 60 toabout 99.9 weight percent cf the intercalated clay. Both components areusually in particulate form. The intercalated clay can have been ionexchanged and/or isomorpically substituted with at least one transitionmetal.

The invention further includes a hydroprocessing catalyst composition of0 to about 40 (also 0.1 to about 40) weight percent of at least onezeolite, 0.1 to about 30 weight percent of alumina and the remainder(about 30 to 99.9 weight percent) of the invention intercalated clay.All of the components are usually in particulate form. The intercalatedclay can have been ion exchanged and/or isomorpically substituted withat least one transition metal. The inclusion of alumina provides ahydroprocessing catalyst composition with much enhanced stability.

The intercalated compositions of the invention are types of non-zeoliticmolecular sieves having three dimensional microporous frameworkstructures.

In FIG. 22, there is a schematic of a cross-section of the aluminum-rareearth element-oxygen pillared clay (bentonite) of the invention. In thefigure, d₀₀₁ is the distance between the bottom of two adjacentsilica-alumina clay layers, Pil is an aluminum-rare earth element-oxygenpillar, IL is interlayer spacing or distance and IP is the lateral orinterpillar distance or spacing.

In the subject clays the interlayer distance IL is larger and pillarshave a crystalline structure as shown by X-ray patterns.

In the invention, hydrothermally stable intercalated clay is prepared byreacting a 2:1 layered clay with an oligomer prepared by copolymerizingsoluble rare earth salts with a cationic metal complex of aluminum. Thepreferred 2:1 layered clays have a layer charge, x, of about 0.5 to 1.(Vermiculite has a layer charge, x, of about 1 to 1.5. Also, vermiculiteis not a colloidal clay) Preferably the clay is added to a solution ofthe oligomer.

The intercalated clays of the invention are improved over the prior artbecause they have significantly higher hydrothermal stability thanpreviously made clays as reflected by their higher surface areas andconversions after 1400° F. steaming. In the invention, it is believedthat, for example, if cerium cations are complexed or reacted withaluminum chlorhydroxide, (or, more broadly, with Al cations which havebeen hydrolyzed), the cerium will be incorporated into the structure ofthe oligomer. The invention data implies that this has a stabilizingeffect (perhaps by preventing cation migration through obstruction).Steaming simulates deactivation.

The X-ray diffraction scan of aluminum chlorhydrol exhibits a singlebroad peak whereas the invention exhibits two sharp peaks. This materialis unique over aluminum chlorohydrol for pillaring clay because itproduces a catalyst that has larger pore openings and is morehydrothermally stable.

The invention utilizes polymeric cationic hydroxo inorganic metalcomplexes, polymers or copolymers in the preparation of of the noveloligomers, that is, in conjunction with the soluble rare earth salts.The preferred polymeric cationic hydroxo inorganic metal complexes arebasic aluminum complexes formed by the hydrolysis of aluminum salts,basic zirconium complexes formed by the hydrolysis of zirconium salts,and basic chromium complexes formed by the hydrolysis of chromium salts.The most preferred polymeric cationic hydroxo inorganic metal complexesare the basic aluminum complexes, and the most preferred basic aluminumcomplex is chlorhydrol.

The best way to make this material is to mix aluminum chlorophydrol 24%Al₂ O₃ (tradename Chlorhydrol marketed by Reheis Chemical Co.) withlanthanum chloride such that Al/La=25. This solution is then placed in ateflon Parr bomb at 130C for 4 days. Variations of this procedure is toadjust the pH of the solution or add other ionic species to producedifferent types of oligomers.

The desired alumina containing rare earth oligomer can be formed betweenthe temperatures of 90° and 150° C. (over 104° C. under pressure) for 1to 40 days with 130° C. for 4 days being preferred. The molar ratio ofalumina to rare earth should be between 1 and 100 with 25 beingpreferred. The concentration of the reactants can vary between 24%(saturated) to 2.4% Al₂ O₃ with 24% being preferred.

It is known that the type of rare earth used for formation of theoligomer can have a pronounced affect on the resulting structure. Thecrystallinity of the oligomer (see FIG. 23-26) decreases from lanthanum(most crystalline) to Neodymium (least crystalline).

The structure of this material can be altered by pH and by other ionspresent. The molar ratio of aluminum to chloride of Chlorhydrol(aluminum chlorohydrol) is 2:1. Variations of this ratio will producedifferent structured oligomers as indicated by X-ray diffraction scansof pH adjusted oligomers. Specifically, a solution refluxed such thatCe/OH=11 and Al/Ce=20 produced an oligomer with a X-ray diffraction scanvary different from one without pH adjustment (compare FIG. 24 to FIG.28).

In addition, cations (e.g., iron, nickel, silicon, and magnesium) canmake isomorphic substitutions for aluminum thereby altering thecharacteristics of the oligomer. The extent of replacement is determinedby equilibria. However, substitutions for aluminum is thermodynamicallyfavored by elements of similar size and charge. Other cations such aslithium can also alter the structure depending on their concentrations.Also, anions (phosphate, flouride, hydroxide, and carbonate) candisplace chloride from the oligomer's structure thereby altering itsstructure. Pillared clay resulting from the altered oligomers possessdifferent chemical and physical properties than clay containingunaltered oligomers. For Example, pillared clay containing 1% chlorideis an excellent binder. Pillared clay that has had its chloride removedby carbonate substitution is a very poor binder. Small quantities offluoride (A1/F=1000) in the oligomer can result in pillared clay withdifferent acidity and binding properties.

For example, the aluminum portion of the reactant solution could besubstituted in all or part by zirconium, chromium, and titanium sincethese elements are also know to form large polymeric species.

It is theorized that since aluminum cations species are in equilibriumwith each other as a function of pH, concentration, and temperature itis expected that structures not yet found exists. Any cation that existsat the concentrations and pH range of the alumina-rare earth oligomerand capable of making ismoorphic substitutions for aluminum could becopolymerized and incorporated into that oligomer's structure. However,the basic composition of the oligomer remains aluminum, rare earth,oxygen, and/or a halogen.

The basic aluminum, zirconium and chromium complexes can be used aloneor in combinations. [Any cation, anion or colloidal material that canexist at the concentrations and pH of the salt (e.g., aluminum,zirconium or chromium) that forms an oligomer can be copolymerized andincorporated into the structure of the oligomer. The key is if thespecies obstructs or inhibits cation migration (thereby stabilizing thesystem).]

A suitable class of the inorganic aluminum complexes or polymers arethose having the general formula Al_(2+n) (OH)_(3n) X₆, wherein n has avalue of about 4 to 12, and X is usually C1, Br and/or NO₃. Theseinorganic metal polymers are generally believed to have an averagemolecular weight on the order of from about 2000 and larger.

To date the preferred inorganic aluminum complex has been aluminumchlorhydroxide.

A suitable class of the zirconium complexes used to prepare pillaredinterlayed clay products of the invention has the following generalformula: [Zr₄ (OH)₁₂ (H₂ O)₁₂ ]⁺⁴. Aqueous solutions of zirconylchloride, ZrOCl₂ contain tetrameric hydroxo complexes of the type [Zr₄(OH)_(16-n8) ]^(n+), the charge per Zr atom being n/4.

The preparation of the above-noted aluminum and zirconium complexes andpolymers is generally known to those skilled in the art and isdisclosed, for example, in the following references:

(a) Tsuitida and Kobavashi, J. Chem. Soc. Japan (pure Chem. Sect.), 64,1268 (1943), discloses the reaction of solutions of AlCl₃.6H₂ O or HClwith an excess of metallic aluminum: ##STR1##

(b) Inove. Osuoi and Kanava, J. Chem. Soc. Japan (Ind. Chem. Sec.), 61,407 (1958), discloses that more than an equivalent amount of aluminumhydroxide is reacted with an acid: ##STR2##

(c) H. W. Kohlschuter et al., Z. Anorg. Allgem. Chem., 48, 319 (1941),describes a method wherein alkali is added to an aluminum salt solution:##STR3##

(d) T. G. Cwe Berg. X. Anorg. Allgem. Chem., 269, 213 (1952), disclosesa procedure wherein an aqueous solution of AlX₃ is passed through an ionexchange column of OH-form.

(e) German Patent No. 1,102,713 describes extended heating at about 150°C. of salts, such as AlCl₃.6H₂ O.

(f) A. Clearfield and P. A. Vaughan, Acta Cryst. 9, 555 (1956).

(g) A. N. Ermakov. I. N. Marov. and V. K. Belyaeva, Zh Neorgan, Khim. 8,(7), 1923 (1963).

(h) G. H. Muha and P. A. Vaughan, J. Chem. Phys. 33, 194-9, (1960).

In the above formulae, X is Cl, Br or NO₂.

Zirconium oligomer solutions can be prepared by the method disclosed inR. Burch et al., J. of Cat., 97, (1986), pp. 503-510. For example, solidzirconyl chloride (ZrOCl₂.8H₂ O) on dissolution produces the tetramericion [Zr₄ OH)₈ (H₂ O)16]⁸⁺. This quickly hydrolyses to form cations withlower charge. These cations polymerize slowly at room temperature, andquite rapidly at higher temperatures, eventually resulting in theformation of hydrous zirconia. The degree of polymerization can becontrolled by varying the temperature or time of ageing of the Zrsolution, and the pH of the solution.

Chromium oligomer solutions can be prepared by combining a chromium saltwith a hydroxyl ion source in solution. This solution is aged to allowformation of a sufficient concentration of cationic oligomers. Inpreparing chromium oligomer solutions, chromium salts capable of beingused include the hydrated forms of chromium nitrate, chromium sulfate,and chromium chloride. The ratio of chromium salt to water is obtainedby determination of the concentration of chromium oligomer necessary toproduce a measurable amount of clay layer expansion. Thus, the lowerlimit on the quantity of chromium salt must be ascertained from theresult of the "aging" step described below. The upper limit is thesolubility of the salt in water. The preferred salt is chromium nitratewith a range of 6 to 72 grams per liter of oligomer solution.Furthermore, suitable sources for the hydroxyl ion component of theoligomer include ammonia, lithium hydroxide, sodium hydroxide andpotassium hydroxide. The preferred combination is chromium nitrate andammonia. When using ammonia as the hydroxyl ion source, the upper limiton pH is the largest pH attainable using concentrated ammonia. However,when using LiOH, NaOH or KOH as the hydroxy ion source, the total amountof added hydroxide should be kept below 2 moles per mole of Cr ion inorder to avoid precipitation of chromium oxide.

The chromium oligomer preparation requires an aqueous mixture of atleast one of the chromium salts and one of the hydroxy ion sources. Thismixture also must undergo an aging treatment. Aging is not needed if theclay and oligomer are initially well dispersed.

The clay, in the preparation of the invention intercalated clays,preferably is added to a solution of the oligomer. Slurries,suspensions, dispersions and the like of the clay can also be used.

The hydrolysis-polymerization can be conducted in the presence of a baseor acid which changes the pH of the reaction mixture to a pH rangepreferably of 2.9 to 4.0 for aluminum polymers. The pH of the startingsolution goes to 3.1; one can start at pH 4 and it goes to 3.1; astarting pH of below 3.1 also goes to 3.1, but the pH shift takeslonger. The further away the starting pH is from 3.1, the longer thetime necessary for the formation of the oligomer. Bases, such as,ammonium hydroxide and sodium hydroxide or a base forming reactant suchas magnesium metal, are added to a heated solution of the metal complexin amounts ranging from about 0.5 to 3 equivalents of base perequivalent of complex. Where the hydrolysis polymerization reaction isconducted in the presence of a base, the solutions are usually reactedat a temperature of from about 50° to 100° C. for a period of from about0.1 to 24 hours.

Furthermore, the high molecular weight polymers can be prepared bycopolymerizing an aluminum, zirconium, chromium or other pillaring metalcomplex with a copolymerizing reactant, such as, SiO₃ ⁻², ZrO₂ ⁺² or BO₃⁺³, which can be included in the reaction mixture as sodium silicate,ZrOCl₂, MgCl₃, zirconium chloride, boric acid or sodium borate, forexample. The use of Fe in the oligomer will provide a different type ofcatalyst. The use of Mo in the oligomer will provide a hydrogenationcatalyst. The reactions are conducted in aqueous solutions which containup to 50 percent by weight of solids and are conducted at temperatureson the order of 80° to 190° C. for periods of 1 to 100 hours. Thetemperature is time dependent so the balance of an effective temperaturefor a suitable time should be used. The surface area of the resultantintercalated clay depends upon the solids content in the reactionsolution. For example: a surface area of about 250 m² /g results from asolids content of 40 weight percent; a surface area of about 300 m² /gresults from a solids content of 35 weight percent; and a surface areaof about 400 m² /g results from a solids content of 25 weight percent.

Additional guidance on the production of intercalated materials may beobtained from the following references:

European Published Patent Application No. 130,055 (British PetroleumCo.) describes a stabilized pillared layered clay and a process for itsproduction. This pillared layered clay consists of a layered claypillared by the residue of a material which has reacted with the hydroxogroups of the clay structure. The process steps are reacting undersubstantially anhydrous conditions in an organic solvent, a layered clayhaving desired hydroxo groups associated therewith, and a materialcapable of reacting with the hydroxo groups to leave a residue of thematerial in the form of pillars for the clay.

European Published Patent Application No. 83,970 (British Petroleum Co.)discloses pillared clays prepared by reacting a smectite-type clay, suchas bentonite, with an aqueous solution of a polymeric cationic hydroxoinorganic metal complex, such as chlorhydrol.

U.S. Pat. No. 4,367,163 (Pinnavaia et al.) discloses silica-intercalatedclay. The material is prepared by exchanging at least a portion of thenative metal ions of a swelling clay with complex silicon ions and thenhydrolyzing the complex silicon ions. The intercalated material can beused as a catayst support for a rare earth.

WO 8503016 (British Petroleum Co.) discloses silanized pillaredinterlayered clays and a method of producing it. The clay consists of apillared interlayered clay chemically modified by incorporation thereinof a silicon containing residue. The method comprises the steps offorming the precursor of a pillared interlayered clay, recovering theprecursor of the pillared clay and optionally washing the recoveredprecursor, calcining the precursor obtained in the previous step to formthe pillared interlayered clay and hydrolyzing a hydrolyzable siliconcompound.

WO 8503015 (British Petroleum Co.) describes a silanized layered clayand a process of its manufacture. The clay consists of a layered claychemically modified by incorporation therein of a silicon-containingresidue in the absence of a polymeric cationic hydroxo inorganic metalcomplex. These clays are produced by hydrolyzing a hydrolyzable siliconcompound, for example, a tetraalkoxysilane, in the presence of thelayered clay and in the absence of a polymeric cationic hydroxo metalcomplex.

U.S. Pat. No. 4,367,163 (Pinnavaia et al.) describes a clay compositionhaving silica intercalated between the interlayers of clay and a methodof preparing it. The main step in the preparation consists of exchangingat least a portion of the native metal ions of a swelling clay withcomplex ions and hydrolyzing the complex ions.

British Patent No. 2,151,603 (British Petroleum Co.) describes apillared layered clay having beryllium containing pillars that isproduced by hydrolyzing a beryllium compound such as a salt andsubjecting this treated compound to cation-exchanging with acation-exchangable layered clay.

U.S. Pat. No. 4,469,813 (Gaaf et al.) discloses preparing pillaredhydroisomerization catalysts by heating from 300° to 450° C. atsubatmospheric pressure, a mixture of nickel synthetic micamontmorillonite with one or more polymerized hydroxy metal complexes,such as, a hydroxo aluminum polymeric solution.

U.S. Pat. No. 4,515,901 (Elatter) discloses a method of preparing aninterlayered pillared clay by mixing a clay with a polar solvent, asoluble carbohydrate, and a soluble pillaring agent, drying the mixture,and then heating the mixture at a temperature between 100° to 600° C. todecompose the carbohydrate and form the interlayered pillared clay. (Thetemperature of stabilization is dependent upon the type of clay. Thedehydroxylation temperature is different for each type of clay.)

In the invention, the above-described methods of preparing aluminum,zirconium, chromium and other metal complexes are modified to includethe use of at least one rare earth salt therein.

Any suitable soluble rare earth salt can be used, although water solublerare earth salts are preferred. The preferred water soluble rare earthsalt is LaCl₃. A preferred class of water soluble rare earth salts isthe water soluble cerium salts, although the most preferred class is thewater soluble lanthanum salts. The most preferred soluble rare earthsalt is LaCl₃, and CeCl₃ is the next preferred. But it must be notedthat in nature the rare earths usually occur in mixed form (with Cebeing most plentiful and La next plentiful in such mixtures) and areexpensive to separate, so in commercial usage of the invention mixturesof rare earth salts would most likely be used. Accordingly, mixtures ofrare earth salts are most important in the invention from a commercialviewpoint.

The rare earths are the metallic oxides of the rare earth elements (orrare earth metals). The rare earth elements include the lanthanumseries, that is, elements with atomic numbers 57 through 71. (The rareearth elements are chiefly trivalent.) The lanthanium series includesLa, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb and Lu.

The preferred rare earth salts are those wherein the rare earth atom(s)are trivalent (i.e., the +3 oxidation state). Rare earth salts havingrare earth elements of other oxidation states are also useful.(Tetravalent cerium was found in an experiment not to satisfactorilyprovide the beneficial results of the invention, but it is believed thatfurther nonextensive experimentation would readily provide theexperimental parameters for the tetravalent form of Ce and other rareearth elements to be useful within the scope of the invention.)

Examples of suitable soluble rare earth nitrates are La(NO₃)₃, Ce(NO₃)₃,Nd(NO₃)₃, Sm(NO₃)₃, Eu(NO₃)₃, Gd(NO₃)₃, Tb(NO₃)₃, Dy(NO₃)₃, Er(NO₃)₃,Tm(NO₃)₃, Yb(NO₃)₃, Y(NO₃)₃, Sc(NO₃)₃, Y(NO₃)₃ and Sc(NO₃)₃. Examples ofsuitable soluble rare earth halides are the chlorides, bromides, iodidesand fluorides, such as LaBr₃, LaCl₃, LaI₃, CeBr₃, CeCl₃, CeF₃, PrCl₃,PrI₃, NdBr₃, NdCl₃, NdI₃, SmCl₃, EuBr₃, EuI₃, GdBr₃, GdCl₃, GdI₃, TbBr₃,TbCl₃, TbI₃, TbI₃, DyI₃, DyCl₃, DyBr₃, HoI₃, HoCl₃, ErI₃, ErCl₃, ErBr₃,TmI₃, TmCl₃, TmBr₃, YbBr₃ , YbCl₃, YbI₃, LuBr₃, LuI₃, LuCl₃, YCl₃, YI₃,YBr₃ and ScCl₃. Examples of suitable soluble rare earth sulfates are La₂(SO₄)₃, Ce₂ (SO₄)₃, Pr₂ (SO₄)₃, Nd₂ (SO₄)₃, Sm₂ (SO₄)₃, Eu.sub. (SO₄ ₃,Gd₂ (SO₄)₃, Tb₂ (SO₄)₃, Dy₂ (SO₄)₃, Er₂ (SO₄)₃, Yb₂ (SO₄)₃, Y₂ (SO₄)₃,Tb₂ (SO₄)₃, Dy₂ (SO₄)₃. Examples of suitable soluble rare earthselenates are Ce₂ (SeO₄)₃, Pr₂ (SeO₄)₃, Gd₂ (SeO₄)₃ and Dy₂ (SeO₄)₃.Examples of other suitable soluble rare earth salts are cerium oxalate,cerium acetate, praseodymium acetate, neodymium acetate, samariumacetate, samarium bromate, dysporsium bromate, dysporsium acetate,yttrium acetate, yttrium bromate, and ytterbium acetate. The rare earthnitrates and chlorides are preferred because they are the most solubleof the rare earth salts in water. The rare earth salt preferably has atleast a solubility constant, K_(sp), which allows it to go into solutionsufficiently to allow fast oligomer formation.

To provide methods of producing catalysts with large micropores,stabilization of the pillars from thermal degradation was necessary.Incorporation of rare earths into the structure of the oligomersprovides stabilization of the pillars from thermal degradation.

The synthesis of the oligomer is preferably conducted in water. Thesynthesis can be conducted in a non-aqueous organic or inorganicsolvent. Examples of useful non-aqueous solvents are acetone(preferred), benzene, toluene, cyclohexane, hexamethylsiloxane, ethylether, alcohols, such as methyl, ethyl, propyl and benzyl alcohol,ketones, organic acids, their anhydrides or esters, ketones, toluene,nitrobenzene, pyridine, ethylene glycol, dimethyl ether,tetrahydrofuran, acetonitrile and methyl isobutyl ketone. Preferably thenon-aqueous solvent is a strongly polar solvent. The solvent should beinert. Mixtures of solvents can be used, in that one solvent can be usedfor the rare earth salt and another solvent for the metal complex - whendifferent solvents are used, both solvents should be compatible ormiscible.

The oligomer can be prepared in colloidal systems, that is, solid rareearth salts can be used in conjunction with liquid non-solvents.

The pillar forming aspect of the invention uses at least one pillaringmetal which in conjunction with at least one rare earth provideshydrothermal stability and a d₀₀₁ value of at least 19.6 Å, preferablyat least 25 Å and more preferably at least 30 Å. This means that thepillaring metal forms large polymeric cationic hydroxo inorganic metalcomplexes. Aluminum is preferred because it provides such largecomplexes having up to 13 aluminum atoms. Chromium and zirconium alsoprovide suitable, but relatively smaller, complexes. Ti, Mg, As, Sb, Co,Mn and/or Zn, for example, can be used in conjunction with the Al, Cr,and Zr and/or other pillaring metals. Pillaring metals must form metalmoieties which hydrolyze and form complexes. Aluminum chlorhydroxide anda soluble rare earth salt provided a d₀₀₁ value of 27.4 Å, which doubledthe pore opening as opposed to the use of aluminum chlorhydroxide byitself. When the aluminum complexes are used, even after steaming (100percent) at 1400° F. for 5 hours, the surface areas of about 400 m² /cm.remains and the 27.4 Å pore size stays with a unique intensity.

The observation of temperature effects on the d₀₀₁ spacing is aconvenient way to investigate the thermal stability and hydrothermalstability of an interlayered clay. Bragg's equation (or law) as appliedin pillared clays is:

    nλ=2d·sinθ

wherein n is the repeat number, λ is 1.5418, d is d₀₀₁ and θ is theangle of incidence.

Cationic oligomers, as indicated above, form at a pH of about 3.1.Copolymerization and hydrolysis can occur at a pH of up to about 8.These pH values hold for aluminum-rare earth element-oxygen oligomers.

Generally, low C1 and iron levels in the oligomers are desired. Forexample, iron is a poison that prevents or hinders product formation(and causes coke formation). So C1 and iron should be removed by washingto as low levels as possible.

The clays or lamellar materials which can be utilized as startingmaterials for the clay product of the invention are those colloidallattice clay minerals and their colloidal synthetic analogues which arecapable of swelling. A suitable natural swellable clay ismontmorillonite; the suitable synthetic swellable clays are certainfluorhectorites. Suitable clays include the expandable smectites, aswell as synthetic forms thereof such as reduced charge montmorillonite.Hofmann et al., Z. Anorg. Allg. Chem., 212, 995-999 (1950), andBrindley. G. W., et al., Clays and Clay Minerals, 19, 399-404 (1971),describe methods of preparing such synthetic clays. Natural or syntheticswellable clays can be used.

The clay preferably has a particle size equal to or less than 2 microns.

The clays useful in the invention are crystalline, expandable, colloidalclays or clay minerals. The clays should be of the three-layer type,namely, sheet structures composed of two layers of silica tetrahedronsand one central dioctahedral or trioctahedral layer. This type of clayincludes equidimensional expanding lattice forms (e.g., themontmorillonite groups, such as montmorillonite and sauconite) and theelongate expanding lattice forms (e.g., the montmorillonite groups, suchas montronite, saponite and hectorite). Vermiculite is not believed tobe useful in the invention. The useful clays can be natural or syntheticforms.

Smectites are 2:1 layered clay minerals that carry a lattice charge andcharacteristically expand when solvated with water and alcohols, mostnotably ethylene glycol and glycerol, and are generally represented bythe formula:

    (M.sup.IV).sub.8 (M'.sup.VI).sub.p O.sub.20 (OH).sub.4

wherein p equals four cations with a+3 charge, equals 6 for cations witha+2 charge, IV indicates an ion coordinated to four other ions, and VIindicates an ion coordinated to six other ions. M is commonly Si⁴⁺,optionally partially substituted by other ions such as Al³⁺ and/or Fe³⁺as well as several other four coordinated ions such as P⁵⁺, B³⁺, Ge⁴⁺,Be²⁺ and the like. M' is commonly Al³⁺ or Mg²⁺, but also can bepartially substituted with hexacoordinate ions, such as Fe³⁺, Fe²⁺, Ni²⁺, Co²⁺, Li⁺ and the like. The charge deficiencies created by thevarious substitutions into these four and six coordinate cationpositions are balanced by one or several cations located between thestructural units. Water can also be coordinated to these structuralunits, bonded either to the structure itself, or to the cations as ahydration shell. When dehydrated, the above structural units have arepeat distance or interlayer spacing of about 9 to 12 Å, as measured byX-ray diffraction. Examples of suitable smectites includemontmorillonite, bentonite, beidellite, hectorite, saponite, sauconite,nontronite, chlorite and analogues thereof. Both dioctahedral andtrioctahedral smectites can be used.

The clays are usually in the alkali metal form, such as, sodiummontmorillonite, with the sodium form being preferred. The clays can bein other metal forms, such as, Ca, other alkaline earth metals, Ce, Ni,Fe, Cr, Be, Ti, B, etc. For example, the montmorillonite used preferablyhas a high Na concentration rather than Ca because the former provideseasier ion exchange and better layer expansion.

Swelling agents, that is, polar molecules, such as water, ethyleneglycol and amines, substantially increase the distance between theinterlamellar layers of clay by absorption of the swelling agent whichenters the intermellar space and in doing so pushes apart the lamellarlayers.

Experimentation has shown that vermiculite is not satisfactory withinthe scope of the invention.

The preferred smectite clays have a layer charge, x, of about 0.5 to 1.

The weight ratio of cerium to aluminum in the prepolymerized solution,measured as CeO₂ :Al₂ O₃, typically ranges from 1:52 to 1:1 without anyapparent affect on the product. That is because only 1:52 is in thefinal pillars (i.e., the excess cerium is lost during washing). If theratio is too high (e.g., 1:78) there is a negative effect on oligomerformation. The temperature for the reaction of a chlorhydrol solution at2.4 weight percent of solids has preferably been between 145° C. andreflux with very satisfactory results (reflux at about 106° C. appearsto be the best). The upper and lower temperature limits are not exactlyknown (but generally range from about 5° to about 200° C.). Within suchpreferred temperature range results can be observed within 24 hours.After 100 hours, the results are identical to those with reaction timesover 1000 hours. After the clay has been intercalated, it can be aged upto 10 days or more without any degradation of the structure. However, ifthe oligomer is cooled to room temperature it should be reacted with theclay within one day to assure a good product (i.e., before the oligomerbreaks down). The ratio of oligomer to clay can vary resulting indifferent materials (i.e., partially or fully intercalated clay) but theoptimum stability is around 3 millimoles of A1 per gram of clay.

The invention includes fully and partially intercalated clays, dependingupon the ratio of oligomer to clay used. Along this line, see theexamples below.

Generally, in preparing the intercalated clay, a solution of theoligomer is first prepared. The solution resulting from the preparationof the oligomer can be used. The clay can be added to the oligomersolution. Water or other inert liquid diluent can be used to prepare theoligomer solution. The clay preferably is added to the oligomersolution. Thorough mixing should be used. The concentration in themixture of the clay suspension and the oligomer solution used to formthe pillars should be sufficiently high to result in the formation ofpillars. The solvents listed above for the oligomer formation can beused as the liquid medium to prepare the clay solution, suspension orslurry, although water is preferred.

The clay concentration in the final mixture, that is to say, aftermixing of the oligomer solution and the initial clay suspension, shouldbe sufficiently high to obviate the handling of large volumes ofmixture, yet not excessively high since too high a clay concentration inthe mixture would make the latter difficult to handle. The clayconcentration in the final mixture preferably ranges from 1 to 20 weightpercent, for example.

If desired, a suitable suspension or flocculating agent, such asammonium carbonate (others can be anionic, for example), can be usedwhen the clay is to be in solution, slurry or suspension form.

In the preparation of the intercalated clay of the invention, a 2:1layered clay substrate is impregnated with the oligomer reactant whichgives rise to a three-dimensional supporting structure (pillars) betweenthe layers of the clay. (The factors which deal with securing uniformpillaring include reaction time, reaction temperature, purity of theclay and clay particle size; these are easily determinable for eacholigomer/clay system.) When the clay is treated with the oligomerreactant, the oligomer diffuses between the layers of the clay and isbound to the layer by ionic bonds (through ion exchange with the nativemetal ions in the clay) or by physical absorption (e.g., of the Van derWaal's or hydrogen bonding). The pillars serve to prop open the claylayers upon removal of water and form an internal interconnectedmicropore structure throughout the interlayer.

The temperature at which the clay is impregnated with the pillaringagent is apparently not critical. Preferably, the temperature used isabout 106° C., although temperatures ranging from the freezing point tothe boiling point of the solution containing the pillaring agent aresatisfactory.

The clay substrate is exchanged with an amount of pillaring agentsufficient to given an intercalated structure. The amount ofintercalated material within the layers should be an amount at leastsufficient to maintain the spacing of the expanded clay (without beingin so large an amount as to prevent the micropore system formation).

The pH of the solution containing the pillaring agent may have to beadjusted to provide for optimum intercalation (e.g., time of formation).

The intercalated clay slurry (based on most systems) is preferably agedfor at least 10 days at room temperature, but economics is a crucialfactor as whether or not to age and for how long. Elevated temperatures,say, 150° F., reduce the aging time period. The intercalated clay slurryshould be washed to remove C1, Fe, etc.

Adverse effects are obtained in the final product from any Na,phosphate, C1 or Fe that is present, so such agents should be removed atthis stage in the preparation.

The pillared interlayered clay can thereafter be separated from thereaction medium by conventional means, such as, by centrifugation,air-drying, freeze-drying or filtration.

The heating and/or calcining step (plus steaming step) are used toremove the solvent and fix the structure of the expanded layer state ofthe clay. The object is to decompose the hydrolyzed metal complexes topillars of table inorganic oxides.

Usually a calcination temperature of 500° to 800° C. or higher is used,although the examples below show a critical effect at 650° C.

Upon calcination, the interlayered metal complex is decomposed to form"inorganic oxide pillars" between the expanded clay layers. Theresulting pillared interlayered clay products possess a uniqueinterconnected internal micropore structure. Calcining at elevatedtemperatures in air or steam also removes the organic moieties in theclay. The temperature of stabilization is dependent upon the type ofclay. The dehydroxylation temperature is different for each type ofclay.

After calcining, the pillars can be defined as discrete/non-continuousinorganic oxide particles.

A representative way of preparing the intercalated clays of theinvention is as follows. 5 parts by weight of 50 percent aluminumchlorhydroxide is mixed with 1 part of 60 percent Ce(NO₃)₃. Thissolution is then placed in a teflon Parr bomb at 130° C. for 100 hours.The contents are then poured into 1000 parts of H₂ O and, under highspeed stirring, 7.5 parts of bentonite is added. The material is thenusually filtered, redispersed with water for one or more additionaltimes, and finally dried, calcined for example at 800° C. for 16 hours.Any suitable and useful treatment and purification steps can be used.The resultant intercalated clay is hydrothermally stable and possessescatalytic activity and selectivity which is eminately suitable for thecracking of heavy feed stocks.

The smectite type clays are capable of layer expansion to form poreswith a different shape than the zeolites. The pillars maintain theexpanded layer state in the clay and leave porosity framed by thepillars and the expanded layers in smectite clays. The resultant poreshave a rectangular type opening due to this framing by the pillars andclay layers. Thus, the pores have a different shape than the zeolites,which are more circular in shape.

The invention intercalated clay preferably has a nitrogen BET surfacearea of about 300 to 600 m² /cm, although even lower surface areas canbe produced by using relative large amounts of clay compared to theoligomer.

The collapse of the prior art pillared clays and the invention pillaredclays is both temperature and time dependent, but the invention pillaredclays can withstand higher temperatures and longer time exposures thanthe prior art pillared clays.

The intercalated clay product of the invention is useful as an absorbentin a variety of applications, or can be used as a catalyst support forvarious catalytically active metals such as a Group VIII metal (e.g.,platinum, palladium, nickel, iron, and cobalt), chromium, molydenum,tungsten, vanadium, tin, germanium, gallium, a rare-earth metal and thelike. It can also be used in the proton form, i.e., with hydrogen andammonium ions present. Moreover, the intercalated product can be used inadmixture with other common adsorbents or matrix materials such assilica, alumina, silica-alumina hydrogel, crystalline aluminosilicatezeolite and the like. The pillared clay can therefore be utilized incombination with zeolite Y, dealuminated zeolite Y, zeolite beta, Lzeolite, etc. The catalysts which can be utilized in the proton form orwhich can be prepared by supporting a catalytically active metal on theintercalated clay product of the invention are especially useful in wellknown catalytic cracking hydrocarbon conversion processes. The metal canbe incorporated within the interlamellar region of the expanded claysubstrate by impregnation and/or as salts which exchange with metal ionsin the clay. Upon reduction with some reducing agent, such as hydrogen,the metal ions are reduced to the metal. An especially useful crackingcatalyst is that formed by supporting hydrogen ions, ammonium ions, anion from Group IB to Group VIII of the periodic chart (but not iron) ormixture thereof in the intercalated clay product of the invention. Theintercalated clay product of the invention is also useful as a molecularsieve adsorbent.

The pillared interlayed clay product ion can be exchanged and/orimpregnated with ions and/or metals of Groups IIB through VIII of thePeriodic Table in order to prepare catalysts. The ion exchange orimpregnation can be done, for example, with aqueous solutions oftetramineplatinum chloride. The metal ions can be placed in the pillarsor on the layers of the clay. This matter is discussed in greater detailbelow.

An especially useful area of utility of the intercalated clay of theinvention is in the conversion of hydrocarbon feedstocks, particularlyheavy cracking oils. In recent years, because of the depletion ofworldwide petroleum feedstocks, attention has been directed to thedevelopment of alternate sources of liquid synthetic fuel and gaseousfuels from raw materials, such as coal, oil shale and tar sands.Likewise, attention is also being directed to better utilization ofnative black oils and petroleum residuals. The conversion of heavypetroleum liquids to distillate products such as gasoline normallyrequires catalytic processing, one of the most important of which beingcatalytic cracking. Molecular sieves have had an important andtremendous impact in petroleum refining in that the use of the same invarious refining operations has improved conversion rates as well asproduct distribution. The catalytic action of molecular sieves ischaracterized by the following features:

(a) Organic substrates are intersorbed in the sieve channel system, thatis, because of the constraining pore size and the concave geometry ofthe internal molecular sieve surface. An incoming molecule is usuallyunder the simultaneous action of an ensemble of surrounding catalyticsites. Consequently, substrate polarization is considerably stronger,that is, activation is easier, compared to that with conventionalcatalysts. Further, as a result of approximation and orientation effectsoperative in the channel systems, intrasorbed reactant molecules are inmany cases favorably juxtaposed, with consequent decrease in theactivation entropy of the reaction.

(b) Incorporation of catalytically active sites or chemically reactivespecies in the molecular sieve framework allows for the design andsynthesis of a wide variety of specific adsorbents, catalysts andpolymeric reagents.

(c) The specific geometry and dimensions of the channel system in agiven molecular sieve catalyst allows for performance of molecular-shapeselective processes.

Because of the unique characteristics of molecular sieves, they havebeen widely used in hydrocarbon conversion processes such as cracking,hydrocracking, isomerization, hydroisomerization, alkylation anddealkylation of simple aromatics. However, there are certain severelimitations with respect to the catalytic applications of priormolecular sieves. In particular, because of the narrow range of criticalpore sizes found in such systems the intrasorption and reaction of bulkyor even medium-sized organic molecules is impossible. For instance, ithas been demonstrated that most of the molecules present in raw coalliquids cannot penetrate into the intercrystalline pores of conventionalzeolite catalysts. Furthermore, certain organic substrates, includingmonocyclic aromatic compounds have exhibited low intracrystallinediffusivity in zeolite media, resulting in poor recoveries and fastcatalyst aging.

The catalysts of the invention are heterogenous catalysts. The processof heterogeneous catalysis require the presence of discrete particlesthrough which the reacting products can be passed under suitableconditions to be converted as required. Depending on the nature of theprocess, the discrete particles can be positioned in a fixed bed, amoving bed, or suspended in the reactants as in the fluid catalyticprocesses.

The invention catalysts have excellent high temperature and hydrothermalstability. They are useful as cracking catalysts, particularly forcracking processes involving large or bulky organic molecules. Theinvention catalysts are petroleum cracking catalysts with shapeselectivities comparable to those of commercial zeolite catalysts.

Processes operating at high temperature, for example, petroleumcracking, operate with feed stocks which result in coke deposition. Suchfeed stocks in many cases contain metals or metal compounds, forexample, nickel and vanadium, which as such or as a result of reaction,are converted into compounds which deposit in the pores of the catalyst.The fine pores will clog more rapidly than pores of greater radius. Thevanadium, etc., contaminants in heavy cracking oil, gasoline and thelike are absorbed and bound by the invention pillared clays, whichdeactivates such clays. Since the invention clays more readily bindsvanadium and the like than zeolites, the invention clays can be used inconjunction with zeolites to protect the zeolites by removing thevanadiaum and like contaminants from the feed.

The intercalated catalysts of the invention have unique surfacecharacteristics making them useful as molecular sieves and as catalystsor as bases for catalyts in a variety of separation, hydrocarbonconversions and oxidative combustion processes. The intercalated clayscan be impregnated or otherwise associated with catalytically activemetals by the numerous methods known in the art and used, for example,in fabricating catalysts compositions containing alumina oraluminosilicate materials.

The intercalated clays can be employed for separating molecular speciesin admixture with molecular species of a different degree of polarity orhaving different kinetic diameters by contacting such mixtures with atleast one of the intercalated clays having pore diameters large enoughto adsorb at least one but not all molecular species of the mixturebased on the polarity of the adsorbed molecular species and/or itskinetic diameter. When the intercalated clays are employed for suchseparation processes, the intercalated clays are at least partiallyactivated whereby some molecular species selectively enter theintracrystalline pore system thereof.

The hydrocarbon conversion reactions catalyzed by the intercalated clayscompositions include: cracking; hydrocracking; alkylation of both thearomatic and isoparaffin types; isomerization (including xyleneisomerization); polymerization; reforming; hydrogenation;dehydrogenation; transalkylation; dealkylation; and hydration. Theintercalated clays are particularly useful in catalyzed hydrocarbonconversion reactions where relatively large hydrocarbon molecules arepresent in the feed.

When the intercalated clay catalysts contain a hydrogenation promoter,such promoter can be platinum, palladium, tungsten, nickel, cobalt ormolybdenum and can be used to treat various petroleum stocks includingheavy petroleum residual stocks, cyclic stocks and other hydrocrackablecharge stocks. These stocks can be hydrocracked at a temperature in therange of between about 400° and about 825° F. using a molar ratio ofhydrogen to hydrocarbon in the range of between about 2 and about 80, apressure between about 10 and about 3500 psig, and a liquid hourly spacevelocity (LHSV) of between about 0.1 and about 20, preferably betweenabout 1.0 and about 10.

The intercalated clay catalysts can also be employed in reformingprocesses in which the hydrocarbon feedstocks contact the catalyst at atemperature between about 700° and about 1000° F., a hydrogen pressureof between about 100 and about 500 psig, a LHSV value in the rangebetween about 0.1 and about 10, and a hydrogen to hydrocarbon molarratio in the range between about 1 and about 20, preferably betweenabout 4 and about 12.

Further, the intercalated clay catalysts which contain hydrogenationpromoters, are also useful in hydroisomerization processes wherein thefeedstock, such as normal paraffins, is converted to saturatedbranched-chain isomers. Hydroisomerization processes are typicallycarried out at a temperature between about 200° and about 600° F.,preferably between about 300° and about 550° F., with an LHSV valuebetween about 0.2 and about 1.0. Hydrogen is typically supplied to thereactor in admixture with the hydrocarbon feedstock in molar proportionsof hydrogen to the feedstock of between about 1 and about 5.

The intercalated clays which are similar in composition to thoseemployed for hydrocracking and hydroisomerization can also be employedat between about 650° and about 1000° F., preferably between about 850°and about 950° F., and usually at a somewhat lower pressure within therange between about 15 and about 50 psig for the hydroisomerization ofnormal paraffins. The contact time between the feedstock and theintercalated clay catalyst is generally relatively short to avoidundesirable side reactions, such as, olefin polymerization and paraffincracking. LHSV values in the range between about 0.1 and about 10,preferably between about 1.0 and about 6.0, are suitable.

The very low alkali metal content (often not measurable by currentanalytical techniques) of the intercalated clays make them particularlywell suited for use in the conversion of alkylaromatic compounds,particularly for use in the catalytic disproportionation of toluene,xylene, trimethylbenezenes, tetramethylbenzenes and larger alkylaromaticcompounds. In such disproportionation processes isomerization andtransalkylation can also occur. The intercalated clay catalysts for suchprocesses will typically include Group VIII noble metal adjuvants aloneor in conjunction with Group VIB metals such as tungsten, molybdenum andchromium which are preferably included in such catalyst compositions inamounts between about 3 and about 15 weight percent of the overallcatalyst composition. Extraneous hydrogen can be, but need not be,present in the reaction zone which is maintained at a temperaturebetween about 400° and about 750° F., a pressure in the range betweenabout 100 and about 2000 psig and a LHSV value in the range betweenabout 0.1 and about 15.

One embodiment of the invention may be characterized as a process forcracking heavy oils under hydrocracking conditions utilizinghydrocracking catalyst comprising as at last one component thereof ahydrothermally-stable clay composition having pillars comprising anoligomer of (a) at least one pillaring metal, (b) at least one rareearth metal and (c) oxygen, intercalated between the layers of at leastone colloidal expandable, swelling layered, lattice clay mineral orsynthetic analogue thereof, wherein said oligomer imparts a surface areaof at least 250 m² /g after hydrothermal treatment at 760° C. for fivehours, when exposed to 100% steam.

The intercalated clay catalysts can be employed in catalytic crackingprocesses wherein such are preferably employed with feedstocks, such asgas oils, heavy naphthas, deasphalted crude oil residues, etc., withgasoline being the principal desired product. Temperature conditions aretypically between about 850° and about 1100° F., LHSV values betweenabout 0.5 and about 10, and pressure conditions are between about 0 psigand about 50 psig.

In terms of catalyst usage and product value, catalytic cracking is themost important unit operation of the petroleum refining industry. In atypical fluid catalytic cracking unit, oil is contacted and vaporized bythe hot fluidized catalyst in either the feed riser line or in thereactor. Cracking occurs in the riser at temperatures between 480° and520° C. Catalyst and cracking products are mechanically separated, andoccluded oil on the catalyst surface is removed by steam stripping at500° to 540° C. Catalyst regeneration is completed by burning of cokedeposits in controlled air at temperatures in the 600° to 700° C. rangein the presence of small amounts of water. Then, from the regenerator,the catalyst flows into the incoming oil for reutilization. Catalyststability at the thermal and hydrothermal conditions required forregeneration is essential for the maintenance of high activity and iscritical in determining the commercial importance of a crackingcatalyst.

The intercalated clay catalysts can be employed for dehydrocyclizationreactions which employ paraffinic hydrocarbon feedstocks, preferablynormal paraffins having more than 6 carbon atoms, to form benzene,xylenes, toluene and the like. Dehydrocyclization processes aretypically carried out using reaction conditions similar to thoseemployed for catalytic cracking.

The intercalated clay catalysts can be employed in catalyticdealkylations where paraffinic side chains are cleaved from aromaticnuclei without substantially hydrogenating the ring structure at arelatively high temperatures in the range between about 800° and about1000° F. and at a moderate hydrogen pressure between about 300 and about1000 psig, with the other conditions being similar to those describedabove for catalytic hydrocracking. The intercalated clay catalysts forcatalytic dealkylation are of the same type described above inconnection with catalytic dehydrocyclization. Particularly desirabledealkylation reactions contemplated herein include the conversion ofmethylnaphthalene to naphthalene and toluene and/or xylenes to benzene.

The intercalated clay catalysts can be used in catalytic hydrofiningwherein the primary objective is to provide for the selectivehydrodecomposition of organic sulfur and/or nitrogen compounds withoutsubstantially affecting hydrocarbon molecules present therewith. Forthis purpose it is preferred to employ the same general conditionsdescribed above for catalytic hydrocracking. The catalysts are typicallyof the same general nature as described in connection withdehydrocyclization operations. Feedstocks commonly employed forcatalytic hydroforming include: gasoline fractions; kerosenes; jet fuelfractions; diesel fractions; light and heavy gas oils; deasphalted crudeoil residue; and the like. The feedstock can contain up to about 5weight percent of sulfur and up to about 3 weight percent of nitrogen.

The intercalated clay catalysts can be employed for isomerizationprocesses under conditions similar to those described above forreforming although isomerization processes tend to require somewhat moreacidic catalyst than those employed in reforming processes. Olefins arepreferably isomerized at a temperature between about 500° and about 900°F., while paraffins, naphthenes and alkyl aromatics are isomerized at atemperature between about 700° and about 1000° F. Particularly desirableisomerization reactions contemplated herein include the conversion ofn-heptane and/or n-octane to isoheptanes, iso-octanes, butane toisobutane, methylcyclopentane to cyclohexane, metaxylene and/orortho-xylene to para-xylene, 1-butene to 2-butene and/or isobutene,n-hexene to isohexane, cyclohexane to methylcyclopentene, etc. Thepreferred form is a combination of the intercalated clay with polyvalentmetal compound adjuvants (such as sulfides) of metals of Group IIA,Group IIB and rare earth metals. When employed for dealkylation of alkylaromatics, the temperature is usually at least 350° F. and ranges up toa temperature at which substantial cracking of the feedstock orconversion products occurs, generally up to about 700° F. Thetemperature is preferably at least 450° F. and not greater than thecritical temperature of the compound undergoing dealkylation. Pressureconditions are applied to retain at least the aromatic feed in theliquid state. For alkylation, the temperature can be as low as 250° F.but is preferably at least 350° F. In the alkylation of benzene, tolueneand xylene, the preferred alkylation agents are olefins such as ethyleneand propylene.

The intercalated clays of the invention can be used as hydroprocessingcatalysts when they contain, as incorporated components, differentcombinations of catalytically active transition metal derivativespossessing high hydrogenolytic and/or hydrogenation activity, such as,in particular oxygen and/or sulfur containing oligomers and/oroligomeric cations, and/or simple or complex cations of Mo, Cr, Ni, Co,W and other transition metals. The catalytically-active components canbe in the form of oligomers intercalated in the interlamellar spacebetween the pillars of the invention intercalated clays. Thecatalytically active oligomeric components can be intercalated hydroxo-Mor sulfhydro-M oligomers or oligomeric cations, where M is Mo, Cr, Ni,Co, W or various combinations of these transition metals. Theinterlamellar space also contains exchangeable metallic ion or H+sites.Catalysts of this type can be prepared by a two-step procedure, asfollows:

Step 1. Low molecular weight hydroxo-M oligomers, where M is Ni, Co, Cr,Mo or other transition metal, are prepared under mildly acidicconditions (pH in the range of 2.5 to 6) and introduced into theinterlamellar space of the clay, yielding intermediate intercalationproducts with low d(₀₀₁) values.

Step 2. The intermediate product obtained in Step 1 is subjected topillaring with aluminum-rare earth element-oxygen oligomers to providelarge d₀₀₁ values.

In a slightly modified step 1 of the above procedure, the low molecularweight hydroxo-M oligomers are incorporated into the interlameller spaceof the clay by intercalation of M halides, where M is Ni, Co, Cr, Mo orother transition metal, followed by titration with an aqueous NaOHsolution and consequent in-situ hydrolysis of the M halides tocatalytically active hydroxo-M oligomers.

The catalytically active components can also exhibit intrinsic acidityassociated with acidic sites on the internal clay surface or on thesurface of the pillars or on both surfaces. The catalytically activecomponents can be exchangeable metallic cations of metals such aschromium, nickel, cobalt, molybdenum, tungsten, platinum, palladium,zinc, tin, germanium, copper and gallium and combinations thereof.

The catalytically active components can be in the form of oxides (suchas, Mo oxide) mounted (superimposed) on the pillars. In addition, thecatalyst form can contain catalytically active interlamellar cations, inparticular Ni²⁺ and/or Co²⁺, and/or H⁺. Other transition metal cationscan be present. Preparation of hydroprocessing catalysts of this typecan be performed using a stepwise procedure as follows:

Step 1. The starting clay is subjected to ion-exchange with a transitionmetal ion, in particular Ni²⁺ or Co⁺. Partial ion exchange with acidicions, e.g., Ce³⁺, La³⁺, NH₄ ⁺ (H⁺), is also done in some preparations toincrease the acidity of the ion-exchanged clay.

Step 2. The ion-exchanged clay, such as Nimontmorillonite orCo-monmorillonite is subjected to reaction with aluminum-rare earthelement-oxygen oligomers. (The intercalated clay at this point can beused as a hydroprocessing catalyst.)

Step 3. The intercalated clay from step 2 is subjected to calcination at400° to 450° C. to partially dehydrate and thermally stabilize thepillars.

Step 4. The calcined intercalated clay from step 3 is treated with anaqueous ammonium molybdate solution resulting in chemisorption mountingof Mo oxide on the pillars and, to a minor extent, on aluminol groupspresent at the edges of the clay layers.

The pertinent parts of U.S. Pat. No. 4,579,832 dealing with the aboveprocesses are incorporated herein by reference.

The intercalated clays of the invention can be employed in conventionalmolecular sieving processes as heretofore have been carried out usingaluminosilicate, aluminophosphate or other commonly employed molecularsieves. The intercalated clays are preferably washed and calcined priorto their use in a molecular sieve process to remove any undesirablemolecular species which may be present in the intracrystalline poresystem as a result of synthesis or otherwise.

The intercalated clays of the invention are also useful as adsorbentsand are capable of separating mixtures of molecular species both on thebasis of molecular size (kinetic diameters) and based on the degree ofpolarity of the molecular species. When the separation of molecularspecies is based upon the selective adsorption based on molecular size,the intercalated clay is chosen in view of the dimensions of its pores,such that at least the smaller molecular specie of the mixture can enterthe intracrystalline void space while at least the larger specie areexcluded. When the separation is based on degree of polarity it isgenerally the case that the more hydrophilic intercalated clay willpreferentially adsorb the more polar molecular species of a mixturehaving different degrees of polarity even though both molecular speciescan communicate with the pore system of the intercalated clay.

X-ray patterns of reaction products are obtained by X-ray analysis,using standard X-ray powder diffraction techniques. The radiation sourceis a high-intensity, copper target, X-ray tube operated at 50 Kv and 40ma. The diffraction pattern from the copper K-alpha radiation andgraphite monochromator is suitably recorded by an X-ray spectrometerscintillation counter, pulse height analyzer and strip chart recorder.Flat compressed powder samples are scanned at 2 (2 theta) per minute,using a two second time constant. Interplanar spacings (d) in Angstromunits are obtained from the position of the diffraction peaks expressedas 2r where r is the Bragg angle as observed on the strip chart.Intensities are determined from the heights of diffraction peaks aftersubtracting background, "I_(o) " being the intensity of the strongestline or peak, and "I" being the intensity of each of the other peaks.Alternatively, the X-ray patterns can be obtained by use of computerbased techniques using copper K-alpha radiation, Siemens type K-805X-ray sources and Siemens D-500 X-ray powder diffractometers availablefrom Siemens Corporation, Cherry Hill, N.J.

As will be understood by those skilled in the art, the determination ofthe parameter 2 theta is subject to both human and mechanical error,which in combination, can impose an uncertainty of about+0.4. on eachreported value of 2 theta. This uncertainty is, of course, alsomanifested in the reported values of the d-spacings, which arecalculated from the 2 theta values. This imprecision is generalthroughout the art and is not sufficient to preclude the differentiationof the invention intercalated clay materials from each other and fromthe compositions of the prior art.

As used herein, all parts, ratios, proportions and percentages are on aweight basis and all temperatures are expressed in C., unless otherwisestated herein or otherwise obvious herefrom to one skilled in the art.

In the following examples, unless otherwise stated, the clays used wereHPM-20 (American Colloid Corporation) and Ca-montmorillonite STX-1 (theClay Minerals Society). These clays are high swelling smectites withvarying amounts of alumina. HPM-20 is a bentonite clay and contains 64.3weight percent of SiO₂, 20.7 weight percent of Al₂ O₃, 0.5 weightpercent of CaO, 2.3 weight percent of MgO, 2.6 weight percent of Na₂ O,3.0 weight percent of Fe₂ O₃ and 5.1 weight percent of H₂ O. STX-1 is amontmorillonite clay and contains 71.5 weight percent of SiO₂, 16.1weight percent of Al₂ O₃, 1.3 weight percent of Fe₂ O₃, 0.9 weightpercent of CaO, 3.9 weight percent of MgO, 0.5 weight percent of Na₂ Oand 4.0 weight percent of H₂ O. The purity of these clays is about 90percent; the other 10 percent consists of other minerals, such asfeldspar, gypsum, calcium carbonate and quartz. The sodium and calciumare the principle exchangeable cations that give the raw clay an ionexchange capacity of approximately 100 milliequivalents per 100 g ofsmectite. The clays used in all of the examples were neither purifiednor treated prior to intercalation.

Since nearly all reactions reach equilibrium quicker at highertemperatures, the reactants were either refluxed at 106° C. or a Parrbomb (for temperatures greater than 106° C.) was employed. The reactantsused to synthesize the oligomer were chlorhydrol, 23.8 percent Al₂ O₃,and Ce(NO₃)₃ solution, 29.3 percent CeO₂. In all of the examples,aqueous systems were used.

The intercalated clays were calcined at 1400° F. for 16 hours, (unlessotherwise noted) before characterization. A Philips X-ray diffractionunit model PW1710 with Cu K V radiation was used to determine theposition of the d₀₀₁ peak. The intensity of this peak also helped todetermine the crystallinity of the intercalated material. The surfaceareas were calculated with a Micromeritics Flowsorb II Model 2300 whichutilized the BET isotherm. Finally, the activity of the intercalatedclay was determined by an automated fixed bed microreactor with anin-line Hewlett Packard 5880A gas chromatograph.

EXAMPLES 1 TO 12 Preparation Of Intercalated Clay Using OligomersSynthesized In A Bomb

Bombs were prepared by mixing 20 g of chlorhydrol with 20 g of Ce(NO₃)₃solution in Parr bombs. The bombs were placed in an oven at 125° to 140°C. for 22 to 90 hours. The resultant mixture formed a creamy precipitatethat was partially soluble in water (cerium was in excess and fell outof solution as an insoluble colloidal precipitate). This entire mixturewas added to 3.6 liters of H₂ O containing 30 g of HPM-20, stirred for 1hour, filtered, washed, dried at 115° C., calcined at 800° C. for 16hours, and then steamed at 1400° F. for 5 hours. The data is shown inTable I.

                  TABLE I                                                         ______________________________________                                        Surface Areas of Intercalated Clay Using Oligomers Synthesized                in a Bomb                                                                            Composi-              Surface Area                                                                           Surface Area                                   tion     Bomb         m.sup.2 /g                                                                             m.sup.2 /g                              Example                                                                              of       Temp.   Time 800° C.                                                                         1400° F.                         Number Oligomer °C.                                                                            hrs. 16 hrs.  5 hrs., steam                           ______________________________________                                        1      Al--Ce   125°                                                                           40   277                                              2      Al--Ce   130°                                                                           22   257      171                                     3      Al--Ce   130°                                                                           44   219      220                                     4      Al--Ce   130°                                                                           70   262      279                                     5      Al--Ce   130°                                                                           90   238      254                                     6      Al--Ce   140°                                                                           16   219                                              7      Al--Ce   140°                                                                           40   230                                              8      Al        80°                                                                           285  157                                              9      Al       130°                                                                           90   125                                              10.sup.1                                                                             Al       140°                                                                           22   143                                              11     Al       140°                                                                           22   158                                              12     Al       155°                                                                           168   86                                              ______________________________________                                         Note: .sup.1 Surface area (SA), 500° C., 1 hr., 274 m.sup.2 /g    

Examples 1 to 7 represent the invention and Examples 8 to 12 arecomparative examples. The intercalated clays of Examples 1 to 7 werealso found to be catalytically active by obtaining 52 to 68 percentconversions from standard microactivity tests. In contrast, experimentsperformed as a baseline case (i.e., chlorhydrol only) had significantlylower surface areas. A typical sample had a surface area of 274 m² /gafter heating to 500° C. (below the dehydroxylation temperature), whichindicates well-intercalated material. However, after calcining at 800°C. (above the dehydroxylation temperature) the pillars collapsed asreflected by the absence of the doll peak and the loss of surface areato 143 m² /g concerning two samples synthesized under identicalconditions except that one contained cerium. The difference in theirsurface areas (238 and 125 m² /g , respectively) clearly shows that thepresence of cerium was essential to the overall stability of theintercalated clay.

EXAMPLES 13 TO 18 Preparation Of Intercalated Clay Using OligomersSynthesized From Reflux

A mixture containing 95 percent of chlorhydrol and 5 percent Ce(NO₃)₃solution by weight was brought to reflux (106° C.). At intervals of 24,48 and 192 hours, 120 g rams of reflux was diluted with 2 liters of H₂O, followed by the dispersion of 30 g of HPM-20. This slurry was thenfiltered, redispersed in 4 liters of H₂ O, filtered, dried, and calcinedat 1400° F. for 16 hours. The growth of the oligomer is reflected by thesurface areas after calcination, as shown in Table II.

                  TABLE II                                                        ______________________________________                                        Surface Areas of Intercalated Clay Using Oligomers Synthesized                from Reflux                                                                          Example Number                                                         Data     13       14       15     16   17   18                                ______________________________________                                        Composition                                                                            Al--Ce   Al--Ce   Al--Ce Al   Al   Al                                of oligomer                                                                   Time, hrs.                                                                              24       48      192     24   48  192                               refluxing                                                                     Surface area,                                                                          172      278      416    102  122  103                               1400° F.,                                                              16 hrs., m.sup.2 /g                                                           Surface area,     248      350                                                1400° F.,                                                              5 hrs., steam,                                                                m.sup.2 /g                                                                    ______________________________________                                    

Examples 13 to 15 represent the invention and Examples 16 to 18 arecomparative examples. The comparative examples using only chlorhydrolrefluxed and reacted with clay under identical conditions did notexhibit similar growth to that of the invention examples. Theseexperiments demonstrate the importance of cerium to the stability of theoligomer. In comparison to Examples 1 to 7, it is seen that less ceriumprovides the same results (Al/Ce=52 instead of 2.75) and that such isprobably desirable. In addition, the oligomer can be formed at lowertemperatures enhancing the practicality of the invention synthesis.

EXAMPLES 19 TO 21 X-Ray Diffraction Scans Of Intercalated Clay

One of the fundamental differences between chlorhydrol only andchlorhydrol/cerium prepared intercalated clay is the distance betweenthe unit layers of clay (d₀₀₁ spacing). As can be seen from FIG. 1,water-expanded unreacted clay (HPM-20) (Example 19) has a d₀₀₁ spacingof 9.6 Å. As can be seen from FIG. 2, clay reacted in water witholigomers (Example 20) prepared from chlorhydrol only has a d₀₀₁ spacingof 18.0 Å. The intensity of this peak diminishes as the calcinationtemperature increases. This is especially obvious near thedehydroxylation temperature (about 650° C.) when the pillars collapse.In contrast, clay reacted in water with oligomers prepared fromchlorhydrol/cerium (Example 21) has a d₀₀₁ spacing of 27.4 Å. (See FIG.3). This larger d₀₀₁ spacing is consistent regardless of other reactionconditions (e.g., oligomer synthesis of temperature 106° to 190° and mmmoles of A1 in oligomer per gram of clay is 2, 3 or 5). This data isfound below in Table III. Even oligomer Al/Ce ratios between 4 and 52yield the same d₀₀₁ spacing of 27.4 Å. Therefore, cerium present inconcentrations greater than one part per 52 aluminum atoms is probablyin excess. Also, since no intermediate d₀₀₁ spacings have been observedat various Al/Ce ratios, such finding indicates that one type ofoligomer exists that controls the interlayer spacing. One possiblestructure is that one cerium atom is tetrahedrally bound to 4chlorhydrol (total of 52 Al atoms) molecules.

When the A1 atom to Ce atom ratio was 75:1, the result was unsuccessful.

EXAMPLE 22

The fairly constant difference (23 percent) in surface area observedover the 2 to 8 week period for a given set of runs indicates that thereacted and unreacted oligomers are stable as a function of time or arechanging exactly the same over the period of time. A composite of twosamples was prepared to see if this additional surface area would bereflected in higher microactivity conversions. [A mixture of 2500 g ofchlorhydrol and 500 g of Ce(NO₃)₃ solution was refluxed for 78 days(equilibrium). To secure the first sample, 216 g of reflux was dilutedwith 36 liters of H₂ O to which 270 g of HPM-20 was added. The firstsample was aged for two weeks. To secure the second sample, after agingunder ambient conditions for two weeks, 24 g of reflux was diluted with4 liters of water, to which 30 g of HPM-20 was added and stirred for 1hour. In both cases, the mixture was filtered, redispersed in 4 litersof water, filtered, dried at 130° C. and calcined at 1400° F. for 16hours.] Even though this material was very hydrothermally stable (thesurface area only decreased from 370 to 339 m² /g after 1400° F.steaming), higher conversions were not realized.

EXAMPLE 23 Microactivity Tests Of Intercalated Clay With Normal Feed

Intercalated clays were synthesized under a variety of conditions to seewhat effect they might have on the product distribution frommicroactivity tests (MATS). A suitable microactivity test is the onedescribed in Ciapetta. F. G., and D. Anderson, Oil Gas J., (1967), 65,88. It was found that, regardless of the reaction conditions (e.g.,temperature 106° to 190° C.), the end product gave similar microactivitytest results with a normal feed (KLS-185). (Normal feed KLS-185 was aparaffinic vacuum gas oil, the API gravity at 60 was 27.5, the carbonpercent was 0.15, the initial distillation boiling point was 479° F. andthe 95 percent distillation boiling point was 1005° F.) See Table III.

                  TABLE III                                                       ______________________________________                                        Typical MAT.sup.1 Of Intercalated Clays Synthesized Under Various             Conditions                                                                           Sample Numbers                                                                23-1  23-2    23-3    23-4  23-5  23-6                                 ______________________________________                                        SYNTHESIS                                                                              BOMB    BOMB    BOMB  BOMB  BOMB  BOMB                               CONDI-                                                                        TION                                                                          Al/Ce of 2.75    17.2    9.0   13.7  26    52                                 Reactant,                                                                     Mole Ratio                                                                    SA, POST 279     276     231   321   282   334                                1400° F.,                                                              5 Hrs. Steam.sup.2                                                            Conversions,                                                                           67.6    68.1    64.1  65.3  66.2  69.8                               %.sup.3                                                                       Gas Factor.sup.4                                                                       2.2     1.9     1.5   2.1   2.0   2.2                                H.sub.2 /C.sub.4                                                                       1.7     1.8     2.2   1.8   1.7   1.6                                C.sub.1 -C.sub.4                                                                       13.0    9.4     13.7  12.8  11.7  12.7                               C.sub.4 =                                                                              0.53    0.54    0.40  0.51  0.51  0.47                               Total C.sub.4                                                                 Gasoline,                                                                              49.4    53.9    46.6  47.2  48.1  50.6                               Wt. %                                                                         LCO, Wt. %.sup.5                                                                       26.4    26.0    29.2  27.6  27.1  25.1                               LCO/     81.5    81.3    81.4  79.6  80.1  82.7                               (LCO +                                                                        HCO), %                                                                       HCO,     6.0     6.0     6.7   7.1   6.7   5.3                                Wt. %.sup.6                                                                   Coke, Wt. %                                                                            5.1     4.7     3.8   5.2   6.3   6.6                                Coke Factor.sup.7                                                                      2.4     2.2     2.1   2.7   3.2   2.8                                ______________________________________                                         Notes:                                                                        .sup.1 MAT is microactivity test                                              .sup.2 SA is surface area                                                     .sup.3 Conversion, %, is 100%(HCO wt. % + LCO wt. %)                          .sup.4 Gas factor is calculated by dividing the quantity of gas produced      by the quantity of gas produced by standard catalyst USY at that              particular conversion.                                                        .sup.5 LCO is light cycle oil                                                 .sup.6 HCO is heavy cycle oil                                                 .sup.7 Coke factor is calculated by dividing the quantity of coke produce     by the quantity of coke produced by standard catalyst USY at that             particular conversion.                                                   

Interestingly, when the ratio of Al to Ce was varied from 2.75 to 52, astable oligomer was always formed. Knowing that cerium is essential tothe stability of the oligomer suggests that only a very small quantityof cerium was required. One possible explanation is that one cerium atomis tetrahedrally bound to 4 chlorhydrol (total of 52 A1 atoms)molecules. If this is so, additional cerium would either form fragmentsof the ideal oligomer or be washed out during the rinse. If one assumesthat intercalated clay is inherently similar to all cases, severalconclusions might be reached. First, these catalysts produce a lot ofgas, especially hydrogen. This is due to the presence of contaminantmetals (such as iron) in the clay. Second, the high C₄ =/Total C₄demonstrates the poor hydrogen transfer ability of these catalysts.Third, these catalysts show excellent LCO selectivity (81 percent) overHCO and respectable gasoline plus LCO yields of 76 percent. (LCO islight cycle oil and HCO is heavy cycle oil.) Finally, these catalystsproduce a lot of coke. This high coke factor could be attributed to thelarge pores allowing penetration of coke precursors or from iron in theclay.

It can be generally concluded that the parameters involved with thesynthesis of intercalated clay are not sensitive enough to adverselyaffect the obtaining of a consistent product. However, it should becautioned that different intercalated clays indeed may have been formed,but the normal feed (too light) was unable to differentiate betweenthem.

EXAMPLE 24 Microactivity Tests of Intercalated Clay With Heavy Feed

In order to ascertain any advantage in catalytic activity/selectivityfrom intercalated clay, a heavy ARCO feed (KLS-428) was employed toquantify potential benefits. (The heavy ARCO feed was an aromatic heavyvacuum oil, the API gravity at 60° was 26.2, the carbon percent was1.37, the initial distillation boiling point was 433° F. and the 92percent distillation boiling point was 1055° F.) Spray-dried catalystscontaining the invention intercalated clay neat and with 20 percent ofUSY catalyst (LZY-82) were prepared. These two catalysts, along withDELTA-400 catalyst (KLS-747) as a control, were tested at variouscatalyst/oil (cat/oil) ratios. USY is a designation for an ultra-stableY-type zeolite catalyst, exchanged with rare earths, produced by UOP.DELTA-400* is a trademark for a Y-type zeolite cracking catalystproduced by the Katalistiks unit of UOP.

FIGS. 4 to 10 show activity and selectivity for the three catalysts inthe cracking of ARCO feed. The activity of the intercalated clay/USYmixture was clearly higher than either DELTA-400 catalyst or the neatintercalated clay. A synergistic effect must have been present, sincethe mixed component activity was greater than the sum of the other twoactivities. The invention clay probably intereacts with the heaviermolecules such that molecular traffic to and from the zeolitic componentis facilitated. In FIG. 4, "CAT/OIL" is the weight ratio of catalyst tofeed. In FIGS. 4 to 10 (plus FIG. 11), "clay" means the inventionintercalated clay.

FIG. 5 demonstrates the lower gas (C₁ -C₄) making ability of the mixedcomponent catalyst with respect to DELTA-400 catalyst or the neat clay.Again, a synergism is occurring since neither USY nor neat clay exhibitsuch low gas make.

The liquid yield distributions for these materials shown in FIGS. 6 to 8are also unique. The neat clay makes less gasoline than DELTA-400catalyst at constant conversion because of its greatly enhanced cokemake. However, the mixed component system shows extremely low gas make,resulting in better gasoline selectivity than DELTA-400 catalyst. Bothclay containing catalysts significantly reduce HCO make compared toDELTA-400 catalyst and show improved LCO selectivity. At 67 percentconversion, the mixed component catalyst shows a 17 percent increasewhile the neat clay produces 25 percent more LCO than DELTA-400catalyst. The large less restrictive pore size of the clay isundoubtedly responsible for this difference in LCO/HCO distribution. Thecoke make of the neat clay as shown in FIG. 9 is much greater than theother two catalysts, while the DELTA-400 catalyst produces significantlyless coke than even the mixed component catalyst. The large coke-make isattributable to several factors. First, since the clay probably has weakacidity and large porosity it could readily absorb large molecules whichcould not be cracked but were dehydrogenated or condensed to coke. Thisbehavior would be typical of any system which strongly interacts withlarge aromatic molecules, which do not readily undergo bond rupture.Second, as can be seen in FIG. 10, these clay systems exhibit poorhydrogen transfer ability as reflected in the high olefin to paraffinratio. Part of this is due to the high iron content of the clay, whilepart is also due to its low active site density.

The flexibility of a mixed catalyst system (including the intercalatedclay of the invention) provides a wide range of product distributionsbecause of the different catalytic behavior (i.e., selectivity) betweenintercalated clay and zeolite. The mixed catalyst systems may includeblends of intercalated clay with zeolite and other additives (e.g.,peptized or amorphous alumina). A specific example contains 1 to 60percent intercalated clay, 1 to 40 percent of zeolite catalyst, 1 to 30percent of alumina, with the balance being kaolin. Catalysts of suchmixed component system exhibit optimum LCO selectivity, bottoms crackingand/or heavy metals resistance.

EXAMPLE 25 Effect Of Contaminant Metals On Intercalated Clays

Up to this point in the experiments, the products distributions of theintercalated clays have been very similar regardless of the reactionconditions during synthesis of the oligomer. The coke-make is relativelyhigh (coke factor about 3) compared to USY catalyst containing catalystsusing normal feed (KLS-185). One possible reason is that the pores ofthese clays are larger than conventional cracking catalysts wherebylarger molecules such as coke precursors are no longer restricted.Another contributor to coke could be that the iron present in the claymay be active and responsible for dehydrogenation reactions.

Two clays containing different quantities of iron (montmorillonite Fe₂O₃ was 1.3 percent and HPM-20 Fe₂ O₃ was 3.0 percent) were intercalatedas described in the previous sections. Since coke-make is a function ofactivity, several preparations were made so results could be compared atconstant activity. In FIG. 11, "HPM" is a bentonite clay and "MON" is amontmorillonite clay the higher iron clay produces approximately 65percent more coke than the lower iron clay. Though the data is limited,it appears that every weight percent iron in the clay translates to anadditional 1.2 percent coke (with an iron-free clay producing 1.4percent coke) at 60 percent conversion. Though large pore openings andlow active site density are undoubtedly responsible for some of thecoke-make, the iron in the clay contributes a substantial quantity.

To observe the effect of contaminant metals on intercalated clay thecatalysts described in Example 24 (spray-dried intercalated clay neatand containing 20 percent of USY catalyst were tested for vanadiumpoisoning along with DELTA-400 catalyst as a standard. Vanadiumtolerance of the three catalysts is shown in Table IV.

                                      TABLE IV                                    __________________________________________________________________________    Microactivity Data for the Vanadium Poisoning of Intercalated Clay With       and Without LZY-82                                                                               Sample Number                                                                 25-1                                                                              25-2                                                                              25-3                                                                              25-4                                                                              25-5                                                                              25-6                                                                             DELTA-400                                                                            DELTA-400                                                                            DELTA-400             __________________________________________________________________________    LZY-82, WT. %      0   0   0   20  20  20 30     30     30                    INTERCALATED CLAY, WT. %                                                                         100 100 100 80  80  80 0      0      0                     VANADIUM, WT. %    0   0.5 1.0 0   0.5 1.0                                                                              0      0.5    1.0                   SA, AFTER 1400° F. STEAM 5 HRS.                                                           262 140 51  360 166 78                                     CONVERSION, %      64.1                                                                              37.3                                                                              14.9                                                                              82.4                                                                              63.3                                                                              27.1                                                                             75.4   63.1   33.4                  C.sub.1 -C.sub.4, WT. %                                                                          13.7                                                                              4.6 1.8 15.7                                                                              9.9 2.6                                    GASOLINE, W. %     46.6                                                                              28.5                                                                              11.2                                                                              61.0                                                                              48.5                                                                              24.6                                                                             57.1   49.2   26.3                  LCO, WT. %         29.2                                                                              35.0                                                                              39.4                                                                              145.4                                                                             26.1                                                                              41.5                                                                             18.6   24.4   31.1                  LCO SELECTIVITY    81.4                                                                              55.8                                                                              46.3                                                                              87.9                                                                              71.0                                                                              57.0                                                                             75.6   66.1   46.7                  HCO, WT. %         6.7 27.7                                                                              45.7                                                                              2.1 10.7                                                                              31.3                                                                             6.0    12.5   35.5                  COKE, WT. %        3.8 4.2 4.1 5.7 4.8 4.4                                                                              2.2    2.8    2.4                   __________________________________________________________________________

Neat clay shows very poor vanadium tolerance while the mixed componentsystem is superior (on a zeolite content basis) to DELTA-400 catalyst.Since 20 percent of USY in an alumina matrix without vanadium poisoninggives 68 percent conversion, the preponderant effect of the vanadium ison the clay portion of the mixed component system. It is not knownwhether the drastic loss of conversion between 0.5 and 1.0 weightpercent vanadium for the mixed component results from vanadium attackingthe zeolite or if destruction of the clay produced a diffusional barrierto the zeolite. Vanadium tolerance of a physical blend of USY-containingcatalyst and a neat clay catalyst, therefore, might be superior to theone particle mixture.

EXAMPLES 26 AND 27

An X-ray diffraction scan (FIG. 12) was made of unreacted fluorhectorite(a synthetic clay) which had been expanded by inclusion in water(Example 26). As can be seen from FIG. 12, the unreacted fluorhectoritehas a d₀₀₁ spacing of 12.2 Å. The X-ray diffraction scan data for theunreacted (raw) fluorhectorite is:

                  TABLE V                                                         ______________________________________                                        2Θ, CuKα                                                                         Å    Intensity.sup.1                                       ______________________________________                                         7.238         12.2132  8029                                                  14.555         6.0856   640                                                   19.627         4.5229   207                                                   26.591         3.3521   285                                                   29.376         3.0404   2056                                                  34.429         2.6049   324                                                   36.354         2.4712   357                                                   39.626         2.2744   341                                                   42.473         2.1283   180                                                   44.337         2.0430   300                                                   44.880         2.0196   363                                                   47.028         1.9322   124                                                   53.445         1.7144   198                                                   55.607         1.6527   301                                                   59.999         1.5418   246                                                   61.176         1.5150   638                                                   67.008         1.3966   343                                                   ______________________________________                                         Notes: .sup.1 Intensity is measured in counts per second.                

An X-ray diffraction scan was made (FIG. 13) of intercalatedfluorhectorite (that is, fluorhectorite reacted in water with oligomersprepared from chlorhydrol/cerium), Example 27. As can be seen from FIG.13, the intercalated fluorhectorite has a d₀₀₁ spacing of 25.6 Å. TheX-ray diffraction scan data for the intercalated fluorhectorite is:

                  TABLE VI                                                        ______________________________________                                        2Θ, CuKα                                                                         Å    Intensity.sup.1                                       ______________________________________                                         3.455         25.5722  2654                                                   6.955         12.7084  1230                                                  14.025         6.314    140                                                   17.544         5.0549   147                                                   19.567         4.5367   712                                                   26.597         3.3513   304                                                   28.238         3.165    307                                                   29.143         3.0642   276                                                   34.569         2.5946   478                                                   35.970         2.4967   483                                                   37.797         2.3801   394                                                   39.674         2.2717   353                                                   40.397         2.2327   343                                                   44.036         2.0563   294                                                   53.291         1.7190   356                                                   61.064         1.5175   1168                                                  62.956         1.4763   290                                                   ______________________________________                                    

The pore opening of the intercalated fluorhectorite clay is 13.4 Å (thatis, the difference between the d₀₀₁ value of the intercalatedfluorhectorite and the d₀₀₁ value of the expanded unreactedfluorhectorite). The pore opening of the intercalated bentonite(invention) of Example 21 is 17.8 Å, whereas the intercalated bentoniteof Example 20 is only 8.4 Å.

EXAMPLES 28 TO 35

An X-ray diffraction scan (FIG. 14) was made of oligomers which wereprepared from chlorhydrol in water (Example 28) by refluxing at 106° C.There was no clay present in this example. As can be seen from FIG. 14,the oligomers had a somewhat amorphous d₀₀₁ value of 11 Å. The X-raydiffraction scan data for the oligomers is:

                  TABLE VII                                                       ______________________________________                                        2Θ, CuKα                                                                          Å   Intensity.sup.1                                       ______________________________________                                        4.035           21.8952  98                                                   5.786           15.2730 191                                                   6.752           13.0903 248                                                   7.383           11.9737 296                                                   7.968           11.0955 355                                                   8.570           10.3176 293                                                   9.423            9.3849 210                                                   ______________________________________                                    

FIG. 15 is another X-ray diffraction scan made of oligomers which wereprepared from chlorhydrol in water (Example 29).

An X-ray diffraction scan (FIG. 16) was made of oligomers which wereprepared by refluxing (106° C.) chlorhydrol in an aqueous solution ofCe(NO3)3 for one day (Example 30). The ratio of A1 to Ce was 52:1. Therewas no clay present in this example. As can be seen from FIG. 16, theoligomers had an ordered structure with a d₀₀₁ value of about 20 Å or10.5 Å. The X-ray diffraction scan data for the oligomers is:

                  TABLE VIII                                                      ______________________________________                                        2Θ, CuKα                                                                          Å   Intensity.sup.1                                       ______________________________________                                        4.500           19.6342 219                                                   4.979           17.6342 195                                                   5.863           15.0743 148                                                   7.184           12.3047 179                                                   7.738           11.4249 265                                                   8.894            9.9419 291                                                   12.955           6.8334 107                                                   ______________________________________                                    

An X-ray diffraction scan (FIG. 17) was made of oligomers which wereprepared by refluxing (106° C.) chlorhydrol in an aqueous solution of CeNO₃)₃ for four days (Example 31). The ratio of A1 to Ce was 52:1.

There was no clay present in this example. As can be seen from FIG. 17,the oligomers had an ordered structure with a d₀₀₁ value of about 20 Åor 10.5 Å. The X-ray diffraction scan data for the oligomers is:

                  TABLE IX                                                        ______________________________________                                        2Θ, CuKα                                                                          Å   Intensity.sup.1                                       ______________________________________                                        4.401           20.0791 263                                                   8.453           10.4601 245                                                   ______________________________________                                    

An X-ray diffraction scan (FIG. 18) was made of oligomers which wereprepared by refluxing (106° C.) chlorhydrol in an aqueous solution ofLaCl₃ for 3 months and then drying at room temperature (Example 32). Theratio of A1 to La was 52:1. There was no clay present in this example.As can be seen from FIG. 18, the oligomers had an ordered structure witha d₀₀₁ value of about 20  or 10.5 Å. The X-ray diffraction scan datafor the oligomers is:

                  TABLE X                                                         ______________________________________                                        2Θ, CuKα                                                                          Å   Intensity.sup.1                                       ______________________________________                                        4.606           19.1857 181                                                   5.101           17.3250 250                                                   5.646           15.6531 186                                                   6.791           13.0151 155                                                   8.535           10.3595 283                                                   9.756            9.0660 236                                                   ______________________________________                                    

FIG. 19 is another X-ray diffraction scan made of oligomers which wereprepared by refluxing (106° C.) chlorhydrol in an aqueous solution ofLaCl₃ for 3 months and then air drying (Example 33).

An X-ray diffraction scan (FIG. 20) was made of oligomers which wereprepared by refluxing (106° C.) chlorhydrol in an aqueous solution ofLaCl₃ for 40 days and then drying at room temperature (Example 34). Theratio of A1 to La was 52:1. There was no clay present in this example.As can be seen from FIG. 20, the oligomers had an ordered structure witha d₀₀₁ value of about 20 Å or 10.5 Å. The X-ray diffraction scan datafor the oligomers is:

                  TABLE XI                                                        ______________________________________                                        2Θ, CuKα                                                                          Å   Intensity.sup.1                                       ______________________________________                                        4.228           20.8971 168                                                   7.931           11.1468 176                                                   8.402           10.5238 210                                                   ______________________________________                                    

FIG. 21 is another X-ray diffraction scan made of oligomers which wereprepared by refluxing (106° C.) chlorhydrol in an aqueous solution ofCe(NO₃)3 for 40 days and then air drying (Example 35).

The above data indicates that the Al oligomer changes structure whenrefluxed with the rare earth element Ce or La from a somewhat amorphousd₀₀₁ value of 11 Å to a more ordered structure of about 20 Å (dependentupon the drying temperature and the reflux time).

EXAMPLES 36 TO 38

These examples illustrate the surface areas of various intercalatedclays of the invention after calcining. Various oligomer refluxingpreparation times and clay reaction solution aging times were used.

Several oligomer suspensions were prepared from mixtures (Al/Ce=52:1) ofchlorhydrol and an aqueous solution of Ce(NO₃)₃ (Example 36). Themixtures were refluxed at 106° C. for 1 day. Bentonite (HPM-20) wasdispersed in each of the refluxed oligomer suspensions and aged from 0to 27 days. The following table sets out some of the experimental dataand the surface areas (m² /g ) of the intercalated clays aftercalcination at 1400° F. for 16 hours.

                  TABLE XII                                                       ______________________________________                                        Oligomer Refluxed                                                             1 Day                                                                                               Surface Areas                                           Example                                                                              Weight Ratio Of A                                                                            Reacted Clay Aged, Days                                 No.    In Oligomer To Clay                                                                          0      1    3    9    27                                ______________________________________                                        36-1   4.0 mmoles Al/g clay                                                                         192    197  242  204  240                               36-2   3.0 mmoles Al/g clay                                                                         172    202  235  208  246                               36-2   2.0 mmoles Al/g clay                                                                         114     79  151   47  138                               ______________________________________                                    

In this example, significantly larger surface areas were obtained when 3and 4 mmoles of A1 per gram of clay were used.

Example 36-2, wherein the reacted clay was aged 3 days, had a surfacearea of 110 m² /g after the calcination was followed by 5 hours of steam(100 percent) treatment.

Several oligomer suspensions were prepared from mixtures (Al/Ce=52:1) ofchlorhydrol and an aqueous solution of Ce(NO₃)₃ (Example 37). Anoligomer suspension was also prepared from a mixture of water andchlorhydrol. All of the mixtures were refluxed at 106° C. for 4 days.Bentonite (HPM-20) was dispersed in each of the refluxed oligomersuspensions and aged from 0 to 27 days. The following table sets outsome of the experimental data and the surface areas (m² /g ) of theintercalated clays after calcination at 1400° F. for 16 hours.

                  TABLE XIII                                                      ______________________________________                                        Oligomer Refluxed                                                             4 Days                                                                                              Surface Areas                                           Example                                                                              Weight Ratio Of Al                                                                           Reacted Clay Aged, Days                                 No.    In Oligomer To Clay                                                                          0      1    3    9    27                                ______________________________________                                               Al only                                                                       (baseline case)                                                        37-1   3.0 mmoles Al/g clay                                                                          46    165  175  164  134                                      AL/CE = 52                                                             37-2   3.0 mmoles Al/g clay                                                                         278    258  281  353  328                               37-3   2.0 mmoles al/g clay                                                                         192    118  126  124  156                               37-4   1.5 mmoles al/g clay                                                                         107     76   72   79   88                               37-5   1.0 mmoles al/g clay                                                                          60     47   52   56   61                               ______________________________________                                    

In this example, invention intercalated clays prepared using 2 and 3mmoles of A1 per gram of clay had significantly larger surface areasthan when lesser amounts of A1 were used. This tends to show that widerpores (of the same height) were formed when less A1 was used becausethere were fewer oligomer pillars formed between the expanded claylayers. The fewer the pillars, the larger the pores (due to largerwidths), and hence smaller surface areas. (The d₀₀₁ spacings would havestayed about the same for all of the invention intercalated clays inthis example.)

Microactivity tests using a normal feed were conducted for theintercalated clays of Example 37-2. The test results are set out in thefollowing table.

                  TABLE XIV                                                       ______________________________________                                        Ages of Reflux, Days                                                                       4       4       4     4     4                                    Age of Reacted Clay,                                                                       0       1       3     9     27                                   Days                                                                          SA 1400° F., 16 hrs,                                                                278     258     281   353   328                                  m.sup.2 g                                                                     SA 1400° F., 5 hrs                                                                  245     207     246   348   289                                  steam, m.sup.2 /g                                                             Conversion, %                                                                              60.7    59.2    60.9  65.0  69.8                                 Activity     1.54    1.45    1.55  1.85  2.31                                 Coke, Wt. %  5.46    4.56    4.87  5.60  6.59                                 Coke Factor  3.45    3.05    3.05  2.97  2.83                                 Gas Factor   2.87    2.38    2.08  2.66  2.17                                 H.sub.2 /CH.sub.4                                                                          2.58    2.41    1.89  2.14  1.60                                 SUM C.sub.1 -C.sub.4, Wt. %                                                                10.7    10.5    11.5  12.4  12.7                                 C.sub.4 =/Total C.sub.4                                                                    0.55    0.56    0.51  0.51  0.47                                 Gasoline, Wt. %                                                                            44.4    44.0    44.4  46.9  50.4                                 LCO, Wt. %   29.0    29.8    29.7  27.2  25.0                                 LCO, Selectivity                                                                           73.7    73.1    75.8  77.7  82.7                                 HCO, Wt. %   10.4    11.0    9.47  7.82  5.23                                 ______________________________________                                    

The conversion and activity test results and LCO selectivity valuesincreased and the coke factor and gas factor values decreased as thelength of aging of the reacted clay increased.

Several oligomer suspensions were prepared from mixtures (Al/Ce-52:1) ofchlorhydrol and an aqueous solution of Ce(NO₃)₃ (Example 38). Themixtures were refluxed at 106° C. for 20 days. Bentonite (HPM-20) wasdispersed in each of the refluxed oligomer suspensions and aged from 0to 27 days. The following table sets out some of the experimental dataand the surface areas (m² /g ) of the intercalated clays aftercalcination at 1400° F. for 16 hours.

                  TABLE XV                                                        ______________________________________                                        Oligomer Refluxed                                                             20 Days                                                                                               Surface Areas                                         Example Weight Ratio Of Al                                                                            Reacted Clay Aged, Days                               No.     In Oligomer To Clay                                                                           1       3    9    27                                  ______________________________________                                        38-1    5.0 mmoles Al/g clay                                                                          394     408  438  378                                 38-2    3.0 mmoles Al/g clay                                                                          416     418  431  433                                 38-3    2.0 mmoles Al/g clay                                                                          229     217  223  247                                 ______________________________________                                    

In this example, the intercalated clays containing 3 and 5 moles of A1per gram of clay had significantly larger surface areas than when lesseramounts of A1 were used. Comparison of the 3 mmole of A1 levels inExample 36 to 38 shows that larger reflux times during oligomerpreparation results in larger surface areas.

Microactivity tests using a normal feed were conducted for theintercalated clays of Example 38-2. The test results are set out in thefollowing table.

                  TABLE XVI                                                       ______________________________________                                        Age of Reflux, Days                                                                            20      20      20    20                                     Age of Reacted Clay, Days                                                                      1       3       9     27                                     SA 1400° F., 16 hrs, m.sup.2 /g                                                         416     418     431   433                                    SA 1400° F., 5 hrs steam, m.sup.2 /g                                                    357     349     382   374                                    Conversion, %    67.9    66.1    67.9  68.4                                   Activity         2.12    1.95    2.11  2.17                                   Coke. Wt. %      5.46    6.73    6.37  6.29                                   Coke Factor      2.55    3.40    2.98  2.87                                   Gas Factor       2.07    2.29    2.37  2.22                                   H.sub.2 /CH.sub.4                                                                              1.56    1.62    1.66  1.52                                   SUM C.sub.1 -C.sub.4, Wt. %                                                                    14.6    12.4    13.1  13.8                                   C.sub.4 =/Total C.sub.4                                                                        0.52    0.50    0.52  0.48                                   Gasoline, Wt. %  47.8    46.8    48.3  48.2                                   LCO, Wt. %       26.6    27.7    26.2  25.6                                   LCO, Selectivity 82.9    81.6    81.5  81.1                                   HCO, Wt. %       5.48    6.24    5.96  5.97                                   ______________________________________                                    

EXAMPLE 39

A series of oligomer suspensions was prepared from mixtures (A1/Ce=52:1)of chlorhydrol and an aqueous solution of Ce(NO₃)₃. The mixtures wererefluxed at 106° C. for 4 days. Bentonite (HPM-20) was dispersed in eachof the refluxed oligomer suspensions and aged for 3 days. The series ofintercalated clay suspensions were filtered, dried and calcined at 1400°F. for 16 hours. Some of the intercalated clay suspensions were washed(i.e., redispersed in water and refiltered) at least one time betweenthe filtering and drying steps. The test results are set out in thefollowing table.

                  TABLE XVII                                                      ______________________________________                                        Number of Washings                                                                              S.A., m.sup.2 /g                                            ______________________________________                                        0                  85                                                         1                 277                                                         2                 411                                                         3                 398                                                         4                 371                                                         ______________________________________                                    

The surface areas (S.A.) of the intercalated clays increaseddramatically with the second washing.

EXAMPLE 40

A series of oligomer suspensions were prepared from mixtures(A1/Ce-52:1) of chlorhydrol and an aqueous solution of Ce(NO₃)₃. Theinitial pH of each mixture was varied as set out in the table below. Themixtures were refluxed at 106° C. for 4 days. As shown in the followingtable, the pH of the refluxed oligomer suspensions went to 3.1regardless of the initial pH (within the range tested).

                  TABLE XVIII                                                     ______________________________________                                        Mixture        Initial pH                                                                              Final pH                                             ______________________________________                                        40-1           3.96      3.11                                                 40-2           3.80      3.10                                                 40-3           3.66      3.12                                                 40-4           2.90      3.09                                                 ______________________________________                                    

EXAMPLE 41

An oligomer suspension was prepared from a mixture of chlorhydrol andwater; and an oligomer suspension was prepared from a mixture of(A1/Ce=52:1) of chlorhydrol and an aqueous solution of Ce(NO₃)₃. Bothmixtures were refluxed at 106° C. for 18 days. Bentonite (HPM-20) wasdispersed in each of the refluxed oligomer suspensions and aged for 3days. The intercalated clay suspensions were calcined at 1400° F. for 16hours and treated with steam 100 percent for 5 hours. Microactivitytests using a normal feed were conducted for the intercalated clays. Thetest results are set out in the following table.

                  TABLE XIX                                                       ______________________________________                                                           SA After                                                                      1400° F.                                                      Time     5 hr.,     Mat                                             Oligomer  Refluxed (100%) Steam                                                                             Conversion                                                                            Activity.sup.1                          ______________________________________                                        Chlorhydrol                                                                             18 Days   58 m.sub.2 /g                                                                           25.45   0.34                                    (Al) only                                                                     Chlorhydrol                                                                             18 Days  255 m.sub.2 /g                                                                           67.92   2.12                                    and Ce(NO.sub.3).sub.3                                                        (Al/Ce = 52:1)                                                                ______________________________________                                         Note: .sup.1 Activity, assuming a first order reaction, is the conversion     divided by the quantity (100conversion)                                  

The steam treatment caused the structure of the intercalated clayprepared from chlorhydrol (Al only) to collapse, as shown by its verylow surface area, whereas the structure of the invention intercalatedclay did not collapse, as shown by its much larger surface area. Theactivity of the steam-treated intercalated clay was at least six timesas large as activity of the steam-treated intercalated clay preparedfrom chlorhydrol (Al only).

EXAMPLE 42

Three oligomer suspensions were prepared from mixtures (A1/Ce=13.7:1) ofchlorhydrol solution (50 percent by weight; 23.8 percent Al₂ O₃) and anaqueous Ce(NO₃)₃ solution (29 percent CeO₂). In the mixtures, the CeO₂content was 29 weight percent and the Al₂ O₃ content was 23.8 weightpercent. The mixtures were refluxed at 106° for 101 hours and then aged10 days at room temperature. Bentonite was dispersed in each of therefluxed oligomer suspensions (with the pH of the resultant highly waterdiluted solutions being 4.56) and aged for 3 days. After filtering anddrying, the intercalated clays were calcined for one hour at 500° C. andthe surface areas were measured. The intercalated clays were thencalcined for 16 hours at 800° C. and the surface areas were measured.The calcined intercalated clays were treated with steam (100 percent)for 5 hours at 1400° F. and the surface areas were measured. The testconditions and results are set out in the following table.

                  TABLE XX                                                        ______________________________________                                                     Example No.                                                                   41-1    41-2      41-3                                           ______________________________________                                        Intercalated Clay.sup.1                                                                      40        55        80                                         SA, 500° C., 1 hr.                                                                    300       266       239                                        SA, 800° C., 16 hrs.                                                                  178       183       118                                        WSA            -40.7     -31.2     -50.6                                      SA, 1400° F., 5 hrs.                                                                  202       166       126                                        Steam                                                                         WSA After      +13.5     -9.3      +6.8                                       Steaming, %                                                                   Conversion     58.4      42.3      44.8                                       Activity       1.40      0.73      1.81                                       C.sub.1 -C.sub.4, Wt. %                                                                      10.5      10.1      7.7                                        Gasoline, Wt. %                                                                              43.4      28.6      34.0                                       LCO, Wt. %     29.2      23.43     2.3                                        HCO, Wt. %     12.5      34.32     2.9                                        LCO ×100 40.2      45.0      51.3                                       LCO + Gasoline = A                                                            LCO ×100 70.0      40.6      58.5                                       HCO + LCO = B                                                                 Selectivity, (A + B)                                                                         110.2     85.6      109.8                                      Coke, Wt. %    4.4       3.5       3.1                                        ______________________________________                                         Note: .sup.1 Grams of oligomer per 30 grams of clay.                     

The test data demonstrates that refluxed oligomers (A1/Ce=13.7:1) at aninitial pH will react with expandable clays to yield intercalated clays,which are very hydrothermally stable catalysts.

EXAMPLES 43 TO 49

These examples demonstrate, by the high conversions after steamingachieved thereby, that the ratio of A1/Ce/H₂ O (and as a consequence,the pH) can be varied during the formation of the oligomers over a widerange.

Three oligomer suspensions were prepared from mixtures of chlorhydroland an aqueous solution of Ce(NO₃)₃ (Example 43 to 45). The ratio of A1to Ce to H₂ O is given in the following table. The mixtures wererefluxed at 106° C. for the times indicated in the following table. Theclays (and their amounts) indicated in the following table weredispersed in the oligomer suspensions and aged for 3 days. The reactedclays were filtered, dried, calcined at 760° C. for 16 hours (except forExample 45) and then steamed (100 percent steam at 1400° F. for 5 hours.The test results are set out in the following table.

Four oligomer suspensions were prepared from mixtures of chlorhydrol andan aqueous solution of Ce(NO₃)₃ (Examples 46 to 49). The ratio of A1 toCe to H₂ O is given in the following table. The mixtures were placed inParr bombs at the temperatures and for the times indicated in thefollowing table. The clays (and their amounts) indicated in thefollowing table were dispersed in the oligomer suspensions and aged for3 days. The reacted clays were filtered, dried, calcined at 760° C. for16 hours and then steamed (100 percent steam) at 1400° F. for 5 hours.The test results are set out in the following table.

                                      TABLE XXI                                   __________________________________________________________________________                 Example No.                                                                   43  44   45  46   47   48   49                                   __________________________________________________________________________    Reaction Type                                                                              Reflux.sup.1                                                                      Reflux.sup.1                                                                       Reflux.sup.1                                                                      Bomb.sup.2                                                                         Bomb.sup.2                                                                         Bomb.sup.2                                                                         Bomb.sup.3                           Clay         Mon.sup.4                                                                         HPM-20.sup.5                                                                       Ben.sup.6                                                                         Ben.sup.6                                                                          Ben.sup.6                                                                          Ben.sup.6                                                                          Ben.sup.6                            Ratio Al/Ce/H.sub.2 O.sup.7                                                                5/1/5                                                                             5/1/0                                                                              5/1/5                                                                             20/10/16                                                                           20/20/0                                                                            25/4/20                                                                            20/20/0                              Ratio React. --  24/30                                                                              55/30                                                                             46/30                                                                              40/30                                                                              49/30                                                                              40/30                                Clay                                                                          Time. Hr.    46  305  49  70   90   192  92                                   Sa, 760° C., 16 hr..sup.8                                                           283 286  --  262  238  315  255                                  SA, 1400° F., 5 hr. Steam                                                           123 248  176 279  254  320  253                                  ΔSA, After Steaming, %                                                               --  -13.3                                                                              --  --   --   +1.6 -0.8                                 Conversion   59.4                                                                              65.8 66.1                                                                              67.6 63.9 67.0 64.3                                 C.sub.1 -C.sub.4, Wt. %                                                                    13.5                                                                              11.3 11.2                                                                              13.0 12.4 13.5 11.5                                 Gasoline, wt. %                                                                            43.1                                                                              50.1 50.4                                                                              49.4 46.6 48.0 47.9                                 LCO, Wt. %   29.0                                                                              26.7 25.9                                                                              26.4 29.0 27.0 27.8                                 HCO, Wt. %   11.6                                                                              7.5  8.0 6.0  7.1  6.0  8.0                                  Coke, WT, %  2.7 4.3  4.4 5.1  4.7  5.4  4.8                                  __________________________________________________________________________     Notes:                                                                        .sup.1 Refluxed at 106° C.                                             .sup.2 Temperature was 130° C.                                         .sup.3 Temperature was 145° C.                                         .sup.4 Mon is monmorillonite                                                  .sup.5 HPM20 is a bentonite                                                   .sup.6 BEN is bentonite                                                       .sup.7 The Al was present as an aqueous chlorhydrol solution (50 percent      by weight; 23.8 percent Al.sub.2 O.sub.3). The Ce was present as an           aqueous Ce(NO.sub.3).sub.3 solution (29 percent CeO.sub.2).                   .sup.8 Calcined                                                          

EXAMPLES 50 TO 63

These examples demonstrate that oligomer formation is a function of timeand temperature [that is, 106° C. vs. 130° C. Vs. 145° C. (the latter isless favorable)]. Seven oligomer suspensions were prepared from mixtures(A1/Ce=2.74:1) of chlorhydrol and an aqueous solution of Ce(NO₃)₃(Examples 50 to 56). The mixtures were refluxed at 106° C. for the timesindicated in the following table. The same amount of bentonite wasdispersed in equal amounts of the oligomer suspensions and aged forthree days. The reacted clays were filtered, dried, calcined at 800° C.for 16 hours and then, in Examples 54 to 56, steamed (100 percent steam)at 1500° F. for 5 hours. The test results are set out in the followingtable.

                  TABLE XXII                                                      ______________________________________                                               Example No.                                                                   50  51    52    53   54     55     56                                  ______________________________________                                        Time, hr..sup.1                                                                         0    24    48  72   98     168    192                               SA, 800° C.,                                                                    20    40    90  150  214    221    193                               16 hr..sup.2                                                                  SA, 1500° F.,          89     117    109                               5 hr. Steam                                                                   ΔSA After               -58.4  -47.1  -43.5                             Steaming, %                                                                   Conversion                    38.0   43.8   44.6                              C.sub.1 -C.sub.4,             5.9    7.0    7.3                               Wt. %                                                                         Gasoline, Wt.                 29.6   33.9   34.6                              LCO, Wt. %                    33.2   33.9   32.5                              HCO, Wt. %                    28.8   22.3   22.9                              LCO ×100                                                                LCO + Gas-                    52.9   50.0   51.6                              oline = A                                                                     LCO ×100                                                                HCO +                         53.5   60.3   58.7                              LCO = B                                                                       Selectivity,                  106    110    110                               (A + B)                                                                       Coke, Wt. %                   2.4    2.8    2.6                               ______________________________________                                         Notes:                                                                        .sup.1 Reflux time                                                            .sup.2 Calcined                                                          

Four oligomer suspensions were prepared from mixtures (A1/Ce=2.74:1) ofchlorhydrol and an aqueous solution of Ce(NO₃)₃ (Examples 57 to 60). Themixtures were placed in Parr bombs at 130° C. for the times indicated inthe following table. The same amount of bentonite used above in Examples50 to 56 was dispersed in the same amounts of the oligomer suspensionsused above in Examples 50 to 56 and aged for 3 days. The reacted clayswere filtered, dried, calcined at 800° C. for 16 hours and then steamed(100 percent steam) at 1500° F. for 5 hours. The test results are setout in the following table.

                  TABLE XXIII                                                     ______________________________________                                                      Example No.                                                                   57     58      59      60                                       ______________________________________                                        Time, hr..sup.1 22       44      70    90                                     SA, 800° C., 16 hr..sup.2                                                              257      219     262   238                                    SA, 1500° F., 5 hr. Steam                                                              171      220     279   254                                    WSA After Steaming, %                                                                         -33.5    -0.5    6.5   6.7                                    Conversion      51.7     61.9    67.6  63.9                                   C.sub.1 -C.sub.4 Wt. %                                                                        8.9      12.1    13.0  12.4                                   Gasoline, Wt. % 38.6     44.9    49.4  46.6                                   LCO, Wt. %      32.0     23.2    26.4  29.0                                   HCO, Wt. %      16.3     14.9    6.0   7.1                                    LCO ×100                                                                LCO + Gasoline = A                                                                            45.3     34.1    34.8  38.4                                   LCO ×100                                                                HCO + LCO = B   66.3     60.9    81.5  80.3                                   Selectivity, (A + B)                                                                          111.6    95.0    116.3 118.7                                  Coke, Wt. %     4.1      4.8     5.1   4.7                                    ______________________________________                                         Notes:                                                                        .sup.1 Bomb reaction time at 130° C.                                   .sup.2 Calcined                                                          

Three oligomer suspensions were prepared from mixtures (A1/Ce=2.74:1) ofchlorhydrol and an aqueous solution of Ce(NO₃)₃ (Examples 61 to 63). Themixtures were placed in Parr bombs at 145° C. for the times indicated inthe following table. The same amount of bentonite used above in Examples50 to 56 was dispersed in the same amounts of the oligomer suspensionsused above in Examples 50 to 56 and aged for 3 days. The reacted clayswere filtered, dried, calcined at 800° C. for 16 hours and then steamed(100 percent steam) at 1500° F. for 5 hours. The test results are setout in the following table.

                  TABLE XXIV                                                      ______________________________________                                                      Example No.                                                                   61      62        63                                            ______________________________________                                        Time, hr..sup.1 22        44        92                                        SA, 800° C., 16 hr..sup.2                                                              238       304       255                                       SA, 1500° F., 5 hr. Steam                                                              187       224       253                                       WSA After Steaming, %                                                                         -21.4     -26.3     -0.8                                      Conversion                47.5      64.3                                      C.sub.1 -C.sub.4, Wt. %   9.6       11.5                                      Gasoline, Wt. %           33.4      47.9                                      LCO, Wt. %                26.4      27.8                                      HCO, Wt. %                26.1      8.0                                       LCO ×100                                                                LCO + Gasoline = A        44.1      36.7                                      LCO ×100                                                                HCO + LCO = B             50.3      77.7                                      Selectivity, (A + B)      94.4      114.4                                     Coke, Wt. %               4.4       4.8                                       ______________________________________                                         Note:                                                                         .sup.1 Bomb reaction time at 145° C.                                   .sup.2 Calcined                                                          

EXAMPLES 64-68

Examples 64-68 demonstrate the preference of La as the desired rareearth in the alumina oligomer as shown by its more intense X-raydiffraction peaks.

EXAMPLE 64

22 g of Chlorhydrol and 1.5 g of LaCl₃ (such that mole ratio ofAl:La=26:1) were mixed in a Parr bomb and heated to 130° C. for 88 hoursand dried at 60° C. X-ray diffraction scan of this material is shown inFIG. 23.

EXAMPLE 65

22 g of Chlorhydrol and 1.5 g of CeCl₃ (such that mole ratio ofAl:Ce=26:1) were mixed in a parr bomb and heated to 130° C. for 88 hoursand dried at 60° C. X-ray diffraction scan of this material is shown inFIG. 24.

EXAMPLE 66

22 g of Chlorhydrol and 2.5 g of Pr(NO₃)₃ solution (such that mole ratioof A1:Pr=26:1) were mixed in a Parr bomb and heated to 130° C. for 72hours and dried at 60° C. X-ray diffraction scan of this material isshown in FIG. 25.

EXAMPLE 67

22 g of Chlorhydrol and 2.31 g of Nd(NO₃)₃ solution (such that moleratio of A1:Nd=26:1) were mixed in a Parr bomb and heated to 130° C. for72 hours and dried at 60° C. X-ray diffraction scan of this material isshown in FIG. 26.

EXAMPLE 68

An X-ray diffraction scan was taken of Chlorhydrol dried at 60° C. andis shown in FIG. 27. Material taken from examples 1 through 4 prior tothe bomb treatment exhibited identical X-ray diffraction scans to thatof Chlorhydrol only (FIG. 27).

EXAMPLES 69-72

In examples 69 through 72 it is again demonstrated that La is thepreferred rare earth in the alumina structure as indicated by the higherconversion and post steam surface area.

EXAMPLE 69

44 g of Chlorhydrol and 3.0 g of LaCl₃ (such that mole ratio ofA1:La=26:1) were mixed in a Parr bomb and heated to 130° C. for 88hours. This solution was diluted with 3.5 liters of water to which 68 gof montmorillonite was added and washed until the chloride concentrationwas 0.67%.

EXAMPLE 70

44 g of Chlorhydrol and 3.0 g of that mole ratio of Al:Ce=26 1) weremixed in a Parr bomb and heated to 130° C. for 88 hours. This solutionwas diluted with 3.5 liters of water to which 68 g of montmorillonitewas added and washed until the chloride concentration was 0.64%.

EXAMPLE 71

44 g of Chlorhydrol and SmCl₃ (such that mole ratio of A1:Sm=13:1) weremixed in a Parr bomb and heated to 130° C. for 88 hours. This solutionwas diluted with 3.5 liters of water to which 68 g of montmorillonitewas added and washed until the chloride concentration was 0.11%.

EXAMPLE 72

44 g of Chlorhydrol and 11.1 g of DyCl₃ (such that mole ratio ofA1:Dy=13:1) were mixed in a Parr bomb and heated to 130° C. for 88hours. This solution was diluted with 3.5 liters of water to which 68 gof montmorillonite was added and washed until the chloride concentrationwas 0.47%.

                  TABLE XXV                                                       ______________________________________                                        Activity and Post Steamed Surface Areas for Pillared Clay                     Example #   Conversion %                                                                              Surface Area.sup.1 m.sup.2 /g                         ______________________________________                                        69 (Al--La) 64.5        220                                                   70 (Al--Ce) 61.8        198                                                   71 (Al--Sm) 47.7         78                                                   72 (Al--Dy) 20.6         21                                                   ______________________________________                                         .sup.1 1400° F., 5 hours, 100% steam                              

The following Example demonstrates that the desired oligomer can beformed from a starting solution containing a mole ratio of aluminum torare earth of 2.

EXAMPLE 73

A solution containing 10.94 g of NaOH in 97.4 g of water was added to2585 g of Ce(No₃)₃ (23.0% CeO₂). Then 1480 g of Chlorhydrol (23.8% Al₂O₃) was added (such that the mole ratio A1:Ce=2:1) and brought toreflux. After 12 weeks the solution was cooled and divided into 4 partsfor chemical analysis. The first portion contained no precipitate andwas found to have a mole ratio of A1:Ce=0.23. The top layer ofprecipitate had a mole ration of A1:Ce=10. The middle layer ofprecipitate had a mole ratio of A1:Ce=8.8. And the bottom layer ofprecipitate had a mole ration of A1:Ce=3.7. Precipitate with a moleratio of A1:Ce=10 was suitable for making pillared clay with d₀₀₁spacings of 27A.

What is claimed:
 1. An intercalated smectite clay having pillars whichcomprise at least one rare earth metal, said clay characterized by aninterlayer spacing greater than about 21 angstroms.
 2. The clay of claim1 wherein the pillars comprise an additional metal chosen from the groupconsisting of aluminum, zirconium, and chromium.
 3. The clay of claim 1wherein the clay has an interlayer spacing of about 22-40 angstroms. 4.An intercalated clay having pillars which comprise a rare earth metaland a metal chosen from the group consisting of aluminum, chromium andzirconium and also characterized by an interlayer spacing of about 21-50angstroms.
 5. The clay of claim 4 wherein the pillars contain cerium orlanthanium.
 6. The clay of claim 4 wherein the pillars comprise aluminumand cerium.
 7. The clay of claim 6 wherein said clay is a smectite clay.8. The clay of claim 4 wherein the clay contains at least one metalchosen from the group consisting of molybdenum, tungsten, platinum,palladium, nickel, cobalt, germanium, tin, gallium and chromium.
 9. Theclay of claim 4 wherein the clay is montmorillonite, bentonite,hectorite, beidellite, saponite, nontronite or sauconite.
 10. The clayof claim 4 wherein the clay is fluorhectorite.
 11. A compositioncomprising a zeolite and an intercalated clay having an interlayerspacing greater than about 21 angstroms, with the clay having pillarswhich comprise a rare earth metal and a pillaring metal chosen from thegroup consisting of aluminum, zirconium, chromium and iron.
 12. Thecomposition of claim 11 wherein the rare earth metal is cerium.
 13. Thecomposition of claim 11 wherein the rare earth metal is lanthanum. 14.The composition of claim 11 wherein the interlayer spacing is less thanabout 40 angstroms.